ser 148 extraction apparatus for the quantitative ...€¦ · velp scientifica - ser 148 manual...

10001364/A11

SER 148 Extraction apparatus for the quantitative separation of a substance from a mixture by the use of an organic solvent Operation manual IMPORTANT: READ THE INFORMATION CONTAINED IN THE PRESENT MANUAL BEFORE USING THE UNIT. THE MANUFACTURER DOES NOT ACKNOWLEDGE ANY RESPONSABILITY FOR AN IMPROPER USE OF THE EQUIPMENT, NOT RESPONDING TO DIRECTIONS FOR U SE. The labels applied to the unit warn the user on the dangers to which he is exposed during the use or the maintenance. The labels must be left on the unit and substituted if they are no more readable.

Warn of danger Read carefully the Safety Regulations here below

Caution hot suface!

Do not dispose of this equipment as urban waste

This unit must only be used for laboratory applications SAFETY RULES 1) During operation do not use nearby open flames or electrical equipment which could give raise to sparks in order to avoid fires. 2) The heating plate can reach a temperature of 260°C during the heating phase but it is still hot also during the cooling phase. Hang the heat shield before starting a cycle, to reduce risk. 3) The containers and the materials used during the work must be compatible with the temperature set on the unit. 4) Conform to the data of the table located on the console and presented in the operation manual which prescribes the temperature to be set for the different solvents and which sealing gasket is to be used. CLEANING Always unplug the unit before cleaning. The test tube must be cool. Use a damp cloth and not flammable, not aggressive detergents. PERSONAL PROTECTION EQUIPMENT The equipment used for personal protection must be compatible with the possible dangers deriving from the working materials and from the glass vessels. MAINTENANCE Maintenance by the user must be limited to the aspects described by the manual. Always unplug the unit before performing maintenance. According to the law on products guarantee our instrument must be repaired at our factory, save different agreements with our agents. GUARANTEE Starts from the date of delivery note and is referred to the number of register of the single unit.

Velp Scientifica - SER 148 Manual

10001364/A11

Contents

Forewords 1

Instrument description 2

Checking the instrument as received 2

Assembling and installing 3

Safety rules 4

Description of control panel 6

Programming and starting 7

Print out of the program’s data 9

Choice of heating temperature 10

Flash point 12

Choice of seals 12

Operation cycle 14

Operations at the end of work 16

Maintenance 17

Oxidizing procedure for cleaning glassware 18

Electric scheme 19

Hydraulic scheme 21

Spare parts and accessories 23

Technical Features 24


10001364/A11

Analytical methods

Determination of crude fat in meat and meat products 27

Determination of total fat in meat, fish, cacao and derived products 28

Determination of the total fat content in whole egg 29

Determination of fat content in vegetable proteic substances (oil seeds) 30

Extraction of oil and grease from wastewater 32

Extraction of oil and grease from sludges 33

Extraction of petroleum source rocks 34

Extraction of plasticizer mixtures from vinyl chloride plastics 35

Extraction of rosin from paper and paperboard 36

Extraction of oils from leather 37

Determination of unsaponified and unsaponifiable fat in soaps 38

Extraction of ethanol soluble components from detergent formulations 39

Extraction of finishing oils from textiles and synthetic or natural fibres 40

Organic analytes extraction from soil, sediment, sludges and waste solids in preparation for GC/MS, GC o HPCL analysis 41

Extraction of total fat from milk powder with a preliminary hydrolysis 43

Determination of total fat in cheese 44

Determination of total fat in flour, bread, bakery products and pasta with preliminary acid hydrolysis 45

Determination of oil content in fried potatoes 46

Determination of the fat content in animal feed 47

Determination of the total fat content in dry animal feed 48


10001364/A11 1

Forewords

Extraction by an organic solvent allows in many cases the quantitative separation of a substance or a group of substances (e.g. fat) from a mixture of solids or semisolids. The most widely used technique, all over the world, takes name from the German chemist Franz Soxhlet (1848-1927) professor of chemistry at the High School of Agricolture of Munich (Bayern); it draws by distillation a pure solvent into contact with the mixture to be extracted.

In the case of solid or semisolid mixtures the sample is contained in a porous cellulose or glass fiber extraction thimble which is covered by the pure solvent which drops from an overhanging condenser. From time to time the solvent with the extracted substances is drawn to the distillation vessel by an automatic siphon. The porous thimble retains the fraction of the mixture not soluble in the solvent. The dissolved substance must not be volatile at the boiling temperature of the solvent.

The Soxhlet extraction apparatus has been modified in different aspects, some of which attempting to increase the temperature of solvent coming into contact with the mixture to be extracted, in order to reduce the extraction time. The Velp extraction apparatus uses a two stage procedure, in the first one the thimble to be extracted is directly immersed in the boiling solvent contained in the distillation vessel; after a defined time the thimble is removed from the solvent and hangs below the cooling condenser from which the condensed solvent drops and washes the sample.

This procedure reduces the time required for a complete extraction to 1/4 ÷ 1/6 of that required by a classical Soxhlet analysis. The fields of application include the analysis of food and feed, detergents, rubber and plastic formulations, pharmaceutical products, soil and so on, for soluble compounds as e.g. fats, tensides, plasticizers, pesticides.

The Velp apparatus allows the use of many different solvents, a large fraction of which is recovered at the end of the extraction cycle, reducing to a minimum the related air pollution. The Velp apparatus is manufactured in accordance with the safety standard IP55 that allows a risk free operation.

The manufacturer, engaged in a continuous improvement of his products reserves the right to modify any of their characteristics without notice.


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Instrument description

The unit is designed for the extraction of solid or semisolid materials using solvents according to Randall technique. The technique reduces sharply the extraction times using two phases with a final recovery of the used solvent.

In the first phase the sample containing thimble is immersed in boiling solvent, while in the second phase it is removed from solvent and reflux washed. Finally a large fraction of the solvent is distilled and recovered.

The unit with 3 or 6 places is optimized for manuality and safety. The chosen materials and technical innovation allow the respect of CEI EN 60529 norms with an IP55 degree of protection allowing a use safe of explosions with a limited space requirement.

Checking the instrument as received

When received, after packing removal check the integrity of unit.

The instrument is delivered with 3/6 extraction cups, 3/6 Butyl seals, 3/6 extraction thimbles Ø 33 x 80 mm, 3/6 thimble adapters Ø 33 mm, tubes for hydraulic for water connection, a heat shield and an operation manual.


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Assembling and installing

Connect the instrument to a water tap for cooling water and to a water sink according to the autoadhesive labels on the rear of the instrument (C1):

INLET The plastic tube is made fix by a band fastener. The open water tap must give a flow at the outlet of about 3 l per minute.

DISCHARGE Cooling water to sink.

C1

Connect the instrument to electric main 230 V (or 115 V) with connections for power and ground, protected by an earth leakage circuit breaker, tared for 0,5 A (C2).

The connection to socket by cable and plug must be at least 1.5 m far from the instrument. Use the plug just installed at factory. The power capacity should be 10 A.

It is not necessary that the equipment is placed in a forced ventilation environment (e.g. a fume hood). Do not use it without an adeguate air circulation to vent or in presence of points of danger like flames or electric sparks.

C2


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Safety rules

Safety devices

All electric components are protected according to IP 55 standards, assuring a complete separation from solvents.

The equipment is protected against overheating by an electronic circuit with an indipendent safety temperature probe. Moreover there is a continuous cross control of the values given by the two temperature probes: when the two temperatures differ more than 20°C thermostatting is interrupted.

The following cases can occur:

1. Interrupted temperature probe circuit. In this condition the temperature of the main probe raises to more than 350°C. If the interrupted circuit belongs to the safety probe, the display shows alternately AL2 and 350.

2. Short circuited probe. The apparent temperature of the probe is less than 2°C. For the main probe the display shows alternately AL1 and 000. If the safety probe is in short circuit the display shows alternately AL2 and 000.

3. Overheating. In this case the temperature of probes corresponds to the value of set point +20°C. For the main probe the display shows alternately AL1 and the temperature of heating plate. If the overheating is noticed by safety probe the display shows alternately AL2 and the temperature of the heating plate.

4. Lack of cooling water. A suitable flowmeter verifies that during operation there is no lack of cooling water necessary for the solvent vapour’s condensation in the glass cooler. If the water mains is not open at the start of a new cycle of work, the cycle will not start, and an acoustic signal is triggered warning of the lack of water, and the visualizer alternatively indicates AL3 and H2O. If a lack of water occurs during the work cycle, the acoustic and visual alarm go off for one minute after which the cycle of work is automatically interrupted and AL3 remains on this display. To restart the corrected operation, press any key.


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Recommendations for handling organic solvents

As in general when handling chemicals, the following precautions should always be observed:

a) Control the risk phrases ( R ) as hazard warning on the containers (e.g. R10 = flammable or R19 = may form explosive peroxides).

b) Always protect eyes and possibly also skin, wearing glasses and gloves.

c) Carry out work as much as possible in a well ventilated environment (e.g. fume hood).

d) Wash immediately with plenty of water any splash on skin or eyes. If necessary seek medical attention.

The supply of organic solvents in the laboratory should be reduced to an indispensable minimum. The solvents not in use should be preserved in metallic cabinets with holes, outside the laboratory. As far as possible it is recommended to avoid the use of most volatile solvents if they can be replaced by a less volatile homologous (e.g. toluene instead of benzene, heptane instead of pentane). Remember that ethers, unsaturated hydrocarbons, aldehydes and ketones are peroxide forming solvents and explosions can occur handling them not only by distillation but also by friction or violent agitation. The control of the presence of peroxides can be performed by easy to use test kits (e.g. Macherey-Nagel Quantofix peroxide test strips, Code CM0091312 and CM0091319).

The destruction of peroxides is not always easy because two phases are formed with water solutions in most of cases which do not allow polymeric peroxides to come into contact with the used reducing agents.

WARNING ! The heating plate and the extract collecting vessels can reach a temperature as high as 260°C (set point). Use tongs to remove the extract collecting vessels at the end of extraction and solvent recovery phases.

Disposal Dispose of in a manner consistent with the laws and regulations of the country and locality in which the unit will be disposed


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Description of control panel

Main switch

Supplies electric power to the unit

Display 1 (upper)

Shows continuously the temperature of heating plate

Display 2 (lower)

Shows all the settable parameter: • Work programs: P01, P02 .… P29 • Set temperature for each program. • Operation times for each program (Immersion, Washing and Recovery). The turning on of corresponding led located on side of display warns about the correspondence of each value.

Leds The turning on of a led shows the correspondence of the value shown by the display: °C Set temperature I Immersion time in boiling solvent W Reflux washing time R Solvent recovery time.

Set key Pressing key Set the letter P (of P01) flashes for a few seconds on the second display, referred to the used work program allowing the choice of a new program by the keys ↑ and ↓.

Key ↵ During programming conferms the value shown by the display. During a work cycle confirms the passage from a time to another.

Key ↑ Increases the value shown by the second display.

Key ↓ Decreases the value shown by the second display.

Key Start/Stop

By pressing this key the chosen program starts. The start of the cycle is warned by the turning on of the corresponding led. By pressing this key during a work cycle this is interrupted.

Key Air Turns on the pump that introduces air in the water cooled condensers. The operation is warned by the turning on of the corresponding led.


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Programming and starting

Turn on the unit by pressing the lighted main switch located on control panel. The upper main display shows the temperature, as °C, of the heating plate, while the lower display shows the number of the last set program.

Choice of program: It is possible to set and choose among 29 work programs composed by: set temperature and three times developed successively with a warning by acoustic signal at the end of each (Immersion, Washing and Recovery). Pressing key Set, letter P flashes on the lower display; afterwards it is possible to select a new program with keys ↑ and ↓.

Setting of program: Each program is composed by four parameters:

1 Work temperature settable from 030 to 260°C 2 Immersion time settable from 000 to 999 minutes 3 Washing time settable from 000 to 999 minutes 4 Recovery time settable from 000 to 999 minutes

Choose the work program to be set and then press the ky ↵ , the led °C turns on and the lower display shows the set temperature, as °C, which can be modified by the keys ↑ and ↓ from 030 to 260°C. Confirm the displayed value by the key ↵, the led I turns on and the display shows the immersion time, in minutes, which can be modified by the keys ↑ and ↓ from 000 to 999 minutes. Confirm the displayed by the key ↵ and repeat the same procedure for the other two times (W Washing and R Recovery) . After confirming the third time, the display shows the number of set program. If only the temperature of heating plate is to be set without the counting of time all the three times are to be setted to 000. If during the setting of a program no key is pressed, after 10 seconds the display returns to show the number of program. If a work cycle is developing it is not possible to modify the parameters of memorized programs nor those of the program in use. Pressing key ↵ brings the lower display to show in succession all the set parameters for the developing program.


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Starting After choosing the desired work program, to start it press the key Start/Stop; the corresponding led will turn on showing the start of activity. The led °C shows that the heating plate is reaching the set temperature, while the lower display shows the number of program in use. When the set boiling temperature is reached the lower display starts to show the decrease of immersion time, in minutes, while the led I (Immersion) turns on (knobs in Immersion position). At the end of immersion time (I Immersion) an acoustic signal warns abort the end of time. To start the count of washing time (W Washing) press the key ↵, the led W turns on and the display shows the decrease of time (knobs in Washing position). At the end of washing time (W Washing) an acoustic signal warns about the end of time. To start the count of recovery time (R Recovery) press the key ↵, the led R turns on and the display shows the decrease of time (closed stopcock = horizontal). At the end of the last time an acoustic signal warns about the end of cycle and the display shows “end”; at the same time the power to heating plate is turned off. If it is wanted to move from one phase to the following without waiting the end of the set time it is sufficient to press the key ↵ . If the temperature of heating plate, at the start of a new cycle, is higher than the set value of the chosen program the cycle does not start with an acoustic warning and with the upper display showing EEE.

Black-Out If during the development of a cycle a lack of electric supply occurs, the restoring of power restarts the equipment in the phase and time existing at the moment of interruption.


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Print out of the program’s data

The instrument is provided with RS232 serial connection through a suitable socket in the front panel in order to print or save the data in files. So all information referring to a programme of work can be printed or saved on file. In addition to the cycle of work the following report can be printed by pressing the following keys at the same time: first ↵ and then SET The Print Report is as follows::

The optional accessories are the following: A00000011 RS232 serial cable for the printer A00001009 Printer The communication protocol of the serial socket is the following: Bits per second 4800 Data bits 8 Parity None Stop bit 1 Flow control No - Xon/Xoff If the print report is to be saved to the computer, the cable code A00000011 and the connector code A00000010 are necessary.

Solvent Extractor Version 1.5 Date: …………….. Time: …………….. Laboratory name: …………………….. Operator Name: ……………………… Sample name: ................................. Lot number: .................................. Program N°: 01 Temperature (°C) 110Immersion time (min.) 30 Washing time (min.) 20 Recover time (min.) 15


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Choice of heating temperature

The temperature of heating plate is to be chosen in relation to the used solvent (see Table).

The difference between the temperature of heating plate and the boiling point of solvent varies from 100°C for those boiling at lower temperatures (e.g. diethyl ether, B.P. 34.6°C) to 260°C for those boiling at higher temperatures.

This is due to the resistance to heat transmission presented by the glass of extraction vessels. It is to be noted that anyway the temperature of heating plate does never reach the ignition temperature of the used solvent.

To avoid to overcome the boiling point, which gives rise to a tumultuous start of boiling, it is indispensable to add to extraction vessels some boiling chips before weighing for tare determination.

Boiling chips (or bumping stones) = small spheres or pieces of glass, small pieces of pumice or silicon carbide.

Temperature of heating plate to be set and type of seal required for some of the mostly used solvents:

Solvent Glass cup

Recommended Temperature °C

Recommended Seal Set

Boiling Point °C

Ignition Point °C

Acetone 160 Butyl 56.5 538

Chloroform 160 Viton 61-62 Not combustible

Diethyl ether 110 Butyl 34.6 180-190

Ethanol 210 Butyl 78.5 423

Ethyl acetate 190 Butyl 77 427

Methanol 210 Viton/Butyl 64.7 470

n-Hexane 130 Viton 69 234

Petroleum ether 110 Viton 30-80 Not specified

Toluene 210 Viton 110.6 536

Trichloroethylene 200 Viton 86.7 Not combustible

If the analysis takes too long the recommended temperature for each solvent can be increased by about 20%


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Commonly used solvents listed by increasing boiling point.

SO

LVE

NT

BO

ILIN

G

PO

INT

°C

FLA

SH

P

OIN

T °C

AU

TO IG

NIT

ION

TE

MP

ER

ATU

RE

°C

DE

NS

ITY

g/

ml a

t 20°

C

VA

PO

UR

P

RE

SS

UR

E

mm

Hg

a 25

°C

SP

EC

IFIC

HE

AT

gcal

/g/°

C

EV

AP

OR

ATI

ON

S

PE

CIF

IC

HE

AT

gcal

/g

Petroleum ether 30 ÷ 80 -40 >200°C 0.662 >400 ~0.500 ~80

Diethyl ether 34.6 -45 180 ÷ 190 0.713 442 0.473 84

Pentane 36.1 -40 (C) 309 0.626 420 0.507 85

Methylene chloride 39.7 - (605) (*) 1.325 340 0.288 60

Acetone 56.5 -18 538 0.788 180 0.538 123

Chloroform 61 ÷ 62 - (*) 1.484 100 0.234 59

Methyl alcohol 64.7 +12 470 0.791 95 0.601 263

Tetrahydrofuran 66 -17 321 0.889 200 0.486 105

n-Exane 69 -40 234 0.660 155 0.600 80

Carbon tetrachloride 76.7 - (*) 1.594 90 0.200 46

Ethyl acetate 77 +7 427 0.902 71 0.476 102

Ethyl alcohol 78.8 +13 423 0.789 42 0.680 204

Methyl ethyl ketone 79.6 -6 516 0.805 71 0.549 106

Benzene (1) 80.1 -11 562 0.879 76 0.419 104

Cyclo hexane 80.7 -18 259 0.778 81 0.520 94

Acetonitrile 81.6 +13 523 0.787 83 0.541 174

Isopropyl alcohol 82.5 +12 456 0.785 32 0.640 159

Trichloroethylene 86.7 - (*) 1.465 60 0.223 57

n-Heptane 98.4 -1 215 0.684 38 0.518 76

Isoctane 99.3 -12 250 0.692 11 0.563 71

Dioxane 101.1 +5 379 1.034 4 0.420 99

Isobutyl alcohol 108 +28 343 0.802 3 0.716 138

Toluene 110.6 +4 536 0.867 24 0.440 87

n-Butyl alcohol 117 +37 343 0.810 13 0.687 141

Acetic acid 118 +39 427 1.050 11 0.522 97

Octane 125.6 +22 210 0.703 12 0.578 73

n-amyl alcohol 138.1 +38 (C) 300 0.817 2 0.711 120

Xilene 138.5 +29 464 0.86 5 0.400 83

(*) not flammable (C) closed cup (1) definitely known to be cancinogenic


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Flash point

The temperature at which a liquid gives off a quantity of vapour sufficient to form an ignitable mixture with the air near the surface of the liquid or within the test vessel.

There are two groups of experimental devices for flash point determination. For the purposes of the official shipping regulations (ICC, OG, IATA) the flash point is determined by the Tagliabue open cup method (ASTM D-1310/63) usually abbreviated TOC. IATA also admits the Abel or the Abel-Pensky closed cup tester.

Other methods used, generally for the higher flash points, are the Tag closed cup and Cleveland open cup. The open cup methods approximate better actual conditions.

Choice of seals

The building materials of retaining seals located between the extraction vessels and the upper parts of the equipment (water cooled condensers) ask for a particular attention due to their chemical resistance to different solvents.

Two materials were chosen: Viton (fluorinated polymer) and Butyl rubber (synthetic rubber) both provided with the instrument.

In general terms Viton is easily dissolved by chetones and esthers, while butyl rubber is attacked by hydrocarbons and halogenated solvents.

Before starting an extraciton it is to be controlled the compatibility of seals for the used solvent (see Table page 12).

Butyl rubber seal WHITE

10000009

Viton seal BLACK

10000008


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It’s available, on request, the Vaflon retaining seal (particular elastomer), resistant to all types of solvents used in extractions, for applications that need particular solvents (or a combination of solvents that would need separately the use of different gaskets).

The Vaflon seal and the Butyl seal are white. The butyl seal shows a little sign on the external diameter that helps to mark the two materials.

Vaflon seal WHITE

A00000061

Butyl rubber seal

WHITE 10000009


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Operation cycle After the installation of the new equipment it is suggested to perform a blank cycle of work with a solvent. This is aimed to remove traces of grease deriving from the assembling which could impair the results of first extractions.

1. Turn on the unit by the general switch located on control panel.

2. Open cooling water tap.

3. Set the temperature of heating plate in relation to the used solvent (see Table page 12). Verify the compatibility of retaining seals.

As delivered the unit is equipped by Viton seals. If the used solvent requires Butyl seals proceed to change as described in “Maintenance”.

4. Introduce samples into thimbles. Connect thimbles to thimble adapters (C3) wearing gloves to avoid contamination (fat).

Introduce thimbles with thimble adapters into the unit (C4) with front knobs in “Immersion” position. Then place the knobs in “Washing” position (C5).

5. Place extraction vessels, preweighted with boiling chips and filled with solvent, into position on the heating plate (C6).

6. Pull down the lever retaining firmly the extraction vessels.

7. Place the glass tap located on condensers in vertical position (open) (C7).

8. Place front knobs in “Immersion” position.

9. Start heating.

10. At the end of extraction in boiling solvent, move the knobs in “Washing” position.

11. At the end of reflux washing, place the glass tap located on condensers in horizontal position (closed) and wait for solvent recovery into lower part of glass condenser.

12. Disconnect the retaining lever and remove glass extraction vessels. Remove extraction thimbles and thimble connectors. Recover solvent placing empty beakers on the heating plate and opening the stopcocks.

C3

C4

C5


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C6 C7

Randall system

Extraction Washing Recovery


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Operations at the end of work

At the end of instrument use:

1. Close the cooling water tap (A6).

2 Turn off the unit by the general switch.

Leave always empty glass beackers on the heating plate to avoid dripping.

A6


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Maintenance

Cleaning of cooling tap water filter Unplug the unit from electric supply and remove the connection to tap water. Remove the cooling water tube from the unit and pull out the filter using small pincers. Clean the filter under flowing water or by compressed air (A11).

Replacement of seals Retaining seals between extraction vessels and glass condensers are to be changed if required by the used solvent. See the table located on the unit or in the present operation manual. Anyway seals are to be replaced if wearied or no more elastic. Get hold of a seal by a small pincer or screwdriver and pull downward (C9). A11 C9


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Oxidizing procedure for cleaning glassware

Glassware can be washed normally using a solution prepared dissolving 30 g of sodium hydroxide (NaOH, technical grade), 10 g of sodium tripolyphosphate (Na5P3O10, technical grade) and 2 g of sodium lauryl sulfate (C12H25NaSO4, commercial mixture).

Glassware can be cleaned by chromic acid oxidation (dichromate and concentrated sulfuric acid), sulfonitric acid oxidation (warm concentrated sulfuric acid with small amounts of potassium or sodium nitrate or nitric acid), or by nitrous oxide oxidation (sodium nitrite and concentrated sulfuric or hydrochloric acids). Chromic-sulfuric acid mixture is prepared adding slowly 1 l of concentrated sulfuric acid (H2SO4, d.1.84, technical grade) to 35 ml of saturated sodium dichromate acqueous solution (Na2Cr2O7, 73% w/w at 20°C, technical grade) while stirring.

The cold mixture must be left into contact with glassware to be cleaned at least 15 minutes, better overnight. The freshly prepared solution is orange red and becomes green after repeated use due to the reduction of Cr VI to Cr III. Exausted chromic-sulfuric mixture must be disposed of in a proper manner due to environmental toxicity of chromium.

Nitrous oxide oxidation of organic residues can be obtained washing the glassware with hot concentrated sulfuric acid (H2SO4, 70%, d. 1.62 technical grade) to which a few drops of saturated sodium nitrite acqueous solution (NaNO2, technical grade, 100 g into 150 ml of tap water) are added before use.

Another method is based on concentrated nitric acid oxidation: the addition of a few drops of ethanol produces after minutes an exotermic reaction and the evolution of oxidizing nitrous oxide.

Attention: all these treatments must be performed under a fume hood due to the extreme toxicity of evolved nitric-nitrous fumes. After oxidizing treatment the filters must be thoroughly rinsed with tap water and finally with deionized water and then dried. Using nitric acid protect hands with PVC gloves and not rubber which is attacked.

Rusting of components

Chlorinated hydrocarbons contain and release on heating traces of very aggressive hydrochloric acid. As a consequence thimble holders and thimble adapters can show some rusting. The very special steel used for these component is slightly attaked by hydrochloric acid.

The rust can be easily removed by immersion of the components in a solution composed by nitric acid, technical grade, concentrated, 2 volumes; hydrochloric acid, technical grade, concentrated, 1 volume; tap water, 5 volumes. By heating the solution to 50-60°C the rust is removed in a few minutes. After rinsing dry the components.


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Electric scheme 230 V/50 Hz

1) General lighted switch 2) Electric board 3) Air pump 4) Heating plate 5) Working Pt100 probe 6) Safety Pt100 probe 7) Male connector 8) Female connector 9) Flow rate 10) RS232 socket


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Electric scheme 115 V/60 Hz

1) General lighted switch 2) Electric board 3) Air pump 4) Heating plate 5) Working Pt100 probe 6) Safety Pt100 probe 7) Male connector 8) Female connector 9) Flow rate 10) RS232 socket 11) Transformer


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Hydraulic scheme Ser 148/3

N° Material Diameter(mm)

Lenght (cm)

Q.ty

1 EPDM 6.4x11.2 25 2 2 EPDM 6.4x11.2 70 1 3 EPDM 6.4x11.2 80 1 4 MQ/MVQ 3x5 30 3 5 MQ/MVQ 3x5 66 1

EPDM = Butyl MQ/MVQ = Silicon


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Hydraulic scheme Ser 148/6

N° Material Diameter(mm)

Lenght (cm)

Q.ty

1 EPDM 6.4x11.2 22 2 2 EPDM 6.4x11.2 25 4 3 EPDM 6.4x11.2 35 2 4 EPDM 6.4x11.2 55 1 5 EPDM 6.4x11.2 70 1 6 MQ/MVQ 3x5 30 6 7 MQ/MVQ 3x5 66 1 8 MQ/MVQ 3x5 97 1

EPDM = Butyl MQ/MVQ = Silicon


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Spare parts

Cod. Art. Cod. Art. Description: 230V/50 Hz 115V/60 Hz 40000428 40000469 Electronic box IP 55

40000201 40000232 Heating plate IP 55 (SER148/3)

40000202 40000233 Heating plate IP 55 (SER148/6)

40000203 40000203 Air pump IP 55

Accessories

Cod. Art. Description: 230V/50 Hz

A00000142 Extraction cups 6 pcs/box

A00001142 Thimble connector Ø 33 mm

10000008 Viton retaining seal

10000009 Butyl rubber retaining seal

A00001145 Handling device for extraction cups

A00001146 Thimble weighing cup

A00001147 Pincer for weighing cups

CM0111148 Pure cellulose extraction thimbles Ø 33x80 mm

A00001149 Thimbles stand (6 places)

10001118 Water cooled glass condenser

A00000061 Vaflon retaining seal


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Technical features SER148/3

General 30300240 F30310240 Power supply V/Hz 230/50-60 115/50-60 Total electric power W 500 Dimensions (WxHxD) mm 480 x 620 x 390 Inch 18,9x24,4x15.5 Weight kg 30 Lb 66 Display 2 display with 3 digit Pollution degree CEI EN61010-1 2 Measurement category CEI EN61010-1 2 Max. admitted humidity T % 85 Storage temperature range °C +5°C……+60°C F +41 +140 Operating temperature range °C +5°C……+40°C F +41 +104 Fuse (T) A 5 10 Performances Reproducibility (RSD) % ≤ 1 Solvent recovery % from 50 to 75 Consumption Cooling water lt/1’ 2 Sample volume g from 0.5 to 15 Solvent volume ml from 30 to 100 for each position Programs Number of programs N° 29 Settable parameters and values: Working temperature from 30 to 260°C Immersion time from 0 to 999 minutes Washing time from 0 to 999 minutes Recovery time from 0 to 999 minutes Safety International protection (EN 60529) IP55 Over temperature 2 internal circuit with 2 separate probe Cooling water Alarm for absence or insufficiency of

cooling water


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Technical features SER148/6

GENERAL F30300242 F30310242 Power supply V/Hz 230/50-60 115/50-60 Total electric power W 950 Dimensions (WxHxD) mm 700 x 620 x 390 Inch 27,5x24,4x15.5 Weight kg 40 Lb 88 Display 2 display with 3 digit Pollution degree CEI EN61010-1 2 Measurement category CEI EN61010-1 2 Max. admitted humidity T % 85 Storage temperature range °C +5°C……+60°C F +41 +140 Operating temperature range °C +5°C……+40°C F +41 +104 Fuse (T) A 5 10 Performances Reproducibility (RSD) % ≤ 1 Solvent recovery % from 50 to 75 Consumption Cooling water lt/1’ 2 Sample volume g from 0.5 to 15 Solvent volume ml from 30 to 100 for each position Programs Number of programs N° 29 Settable parameters and values: Working temperature from 30 to 260°C Immersion time from 0 to 999 minutes Washing time from 0 to 999 minutes Recovery time from 0 to 999 minutes Safety International protection (EN 60529) IP55 Over temperature 2 internal circuit with 2 separate probe Cooling water Alarm for absence or insufficiency of

cooling water


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Flow sheet for a typical extraction of soluble matter by an organic solvent from solid samples

A Grind and homogenize the sample

B Weigh the sample, from 3 to 10 g in relation to the presumed content of extractable matter

C When vegetable or animal protein containing products are examined a preliminary hydrolysis with hydrochloric acid should be performed. Boil one hour in a flask and separate the residue on a paper filter

D Transfer quantitatively the sample or the residue from hydrolysis with the paper filter into the extraction thimble and cover it with a defatted cotton plug

E Introduce the thimble into the extraction equipment

F Weigh the extract collecting vessel with some boiling stones, beforehand dried to constant weight, and introduce it into the extraction equipment

G Add the solvent (30-100 ml)

H Close the extraction unit, start the cooling water flow and the heating.

When the solvent starts boiling immerse the thimble by placing the slider into “Immersion” position

I After 15-60 minutes extract the thimble from solvent placing the slider into “Washing” position

L After 30-60 minutes of reflux washing close the stopcock located under the

water cooled condenser and evaporate completely the solvent from the extraction vessel. If the used solvent has heavy vapour turn on the air pump to improve the displacement to the condenser

M Dry the extract collecting vessel with boiling stones in an oven during 30 minutes at a temperature high enough to evaporate completey solvent residues

N

Cool the extract collecting vessel in a dessicator and weigh it

O Compute the result. The weight of extract is given by the weight of point N less the weight of extract collecting vessel with boiling stones of point F and is to be referred to sample weight as point B


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Determination of crude fat in meat and meat products

The solvent extraction is performed on dried samples.

1) Sample: 3 g of grounded and homogenized material is weighed in an extraction thimble with 1 mg proximation. Total weight-thimble weight = wet sample weight.

2) Chemicals: Petroleum ether 40-60°C, with an evaporation residue not higher than 10 mg/l. Sand: Sea sand or siliceous sand with an extractable content lower than 4 mg/ 5 g. Cotton: defatted cotton wadding Boiling stones.

3) Sample drying: Add some sand to the weighed sample in thimble and mix with a glass rod. Clean the rod with a small flock of defatted cotton and add this to thimble. Dry the thimble 1 hour in a 125°C oven. Remove the thimble from oven and let it cool in a desiccator. Loosen the sample and sand mixture with a glass rod. Clean the rod with a small flock of defatted cotton and place this on top of thimble.

4) Extraction: Accurately weigh the glass extraction cup with a few boiling stones (1 mg proximation). Add 40 ml of petroleum ether. Transfer thimble with sample and sand, assembled with thimble connector to extraction unit.

30 minutes with thimble immersed in boiling solvent 60 minutes of reflux washing

5) Weighing: Dry the extract containing cup with boiling stones in an oven at 125°C during 30 minutes. Let it cool in a desiccator. Weigh to 1 mg proximation.

6) Expression of results: Refer to wet sample as weighed and give the results as crude fat/100 g with two decimal figures.

7) Reference: AOAC. Official Methods of Analysis (1990) 15th Ed. 3rd Supplement 1992. Arlington, Virginia, USA.


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Determination of total fat in meat, fish, cacao and derived products

A preliminary acid hydrolysis is aimed to free occluded or bound lipids

1) Sample: 2 to 10 g of grinded and homogenized matter, weighed in a 250 ml Erlenmeyer flask (with reflux condenser) with 1 mg proximation

2) Chemicals: Hydrochloric acid (HCl) about 4 N, 100 ml of concentrated hydrochloric acid, reagent grade, d. 1.19, mixed with 200 ml of water. Exane or petroleum ether 40-60°C with an evaporation residue not higher than 10 mg/l. Boiling stones.

3) Sample hydrolysis: Add 100 ml of 4 N hydrochloric acid to Erlenmeyer flask with sample. Mix well and after assembling the reflux condenser boil 1 hour, add 100 ml of hot water and filter on a double folded paper filter. Wash three times the Erlenmeyer flask with 60-70 ml of hot water and add the washings to the double filter with hydrolyzed sample. Wash with water until no more acid reaction is shown by filtrate.

4) Sample drying: Place the double filter paper in a 300 ml beaker and place 1-2 hours in an oven at 103°C, together with the Erlenmeyer flask used for the hydrolysis. The dry filters are rolled and introduced in an extraction thimble. The internal of Erlenmeyer flask and beaker are cleaned with a cotton plug soaked in solvent, using forceps. The plug is added to thimble.

5) Extraction: 30-60 ml of the chosen solvent 30 minutes with thimble immersed in boiling solvent 60 minutes of reflux washing Boiling chips

6) Extract drying: Extraction vessel with boiling stones in an oven at 103°C for 30 minutes. Cool in a desiccator.

7) Weighing: The extract containing vessel with boiling stones is weighed to 1 mg proximation after 30 minutes of heating in an oven at 103°C.

8) Expression of result: Refer to wet sample as weighed and give the result as fat g/100 g with one decimal figure

9) Reference: Amtliche Sammlung von Untersuchungsverfahren (1982). (Official Collection of German Analytical Procedures). L 06.00-6. Bestimmung des Gesamtfettgehaltes (Determination of total fat content).


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Determination of the total fat content in whole egg

1) Sample: 5-10g of liquid pasteurized egg are weighed into an Erlenmeyer flask connectable to reflux condenser.

2) Chemicals: hydrochloric acid (HCl) 4N: 100ml of concentrated hydrochloric acid, d.1.19, mixed together with 200ml of deionized water; chloroform (temperature for the heating plate: 160°C) or 1:1 mixture toluene/ethanol (temperature for the heating plate: 210°C), reagent grade. 3) Sample hydrolysis: from 50 (5g sample) up to 100ml (10g sample) of 4N hydrochloric acid. After assembling the water cooled reflux condenser the Erlenmeyer flask is heated to boiling for one hour.At the end of hydrolysis 150ml of deionized water are added to the sample.

4) Sample filtration: a double paper filter soaked with water is used to filter the hydrolyzed sample (Whatman n.o. 42 filtering disks). The hydrolyzed sample is to be cooled at 13-15°C about (using an ice bath) before filtration. The flask used to hydrolyze the sample is to be washed using deionized cool water and the washings are to be poured on the filters. Wash by using cool water until the washings don’t show acid reaction to litmus paper (500ml of washing water are required about).

5) Sample drying: The double paper filter is placed on a watch glass and desiccated in an oven at 102°C for 2 hours together with the flask used for the hydrolysis. The dry filter is rolled and introduced into an extraction thimble. The internal part of flask and watch glass are wiped with filter paper soaked in solvent which is also introduced into thimble. Use forceps.

6) Extraction: 60-70ml of the chosen solvent (according to sample weight).

15 minutes with thimble immersed into boiling solvent

30 minutes of reflux washing

7) Extract drying: place the extraction vessel in an oven at 100°C for 30 minutes. Let cool in a desiccator up to room temperature.

8) Weighing: the extract containing vessel is weighed with a tolerance margin of 1mg.

9) Expression of the results:

% of fat = W3 – W2 / W1 X 100

W1 = sample weight (g); W2 = extraction vessel weight (tare,g); W3 = vessel weight+ residue weight (g).

10) Reference:

AOAC. Official Methods of Analysis. Arlington, Virginia, USA, method 17.012.


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Determination of fat content in vegetable proteic substances (oil seeds)

Fat content is defined as the fraction extractable with a solvent in the conditions suggested for the utilized method. Occluded or bound lipids are freed before extraction by acid hydrolysis.

1) Sample: 5 to 10 g of product grinded to less than 1 mm size, weighed in a 250 ml Erlenmeyer flask (with reflux condenser).

2) Chemicals: Hydrochloric acid (HCl), about 4 N, 100 ml of concentrated hydrochloric acid, d. 1.19, mixed with 200 ml of water.

Diatomaceous flour as filter aid. Exane or petroleum ether 40-60°C with an evaporation residue not higher than 10 mg/l.

Boiling stones.

3) Sample hydrolysis: From 50 (for a 5 g sample) to 100 ml (for a 10 g sample) of 4 N hydrochloric acid. After assembling the water cooled reflux condenser the Erlenmeyer flask is heated to boiling for one hour. At the end of hydrolysis 150 ml of water and about 1 g of filter aid are added to the sample still hot.

4) Sample filtration: A double paper filter soaked with water is used to filter the hydrolyzed sample. The Erlenmeyer flask used for the hydrolysis is washed with hot water and the washings are poured on the filter. Wash with water until the washings do not show acid reaction to turmeric indicator paper.

5) Sample drying: The double paper filter is placed on a watch glass and essiccated in an oven at 102°C for 2 hours together with the flask used for the hydrolysis. The dry filters are rolled and introduced in an extraction thimble. The internal of flask and watch glass are wiped with filter paper soaked in solvent which is also introduced in thimble. Use forceps.

6) Extraction: 30-60 ml of the chosen solvent (according to sample weight)

Boiling stones

15 minutes with thimble immersed in boiling solvent

30 minutes of reflux washing.

7) Extract drying: Extraction vessel with boiling stones in an oven at 100°C for 30 minutes. Cool in a desiccator.

8) Weighing: The extract containing vessel with boiling stones is weighed to 1 mg proximation.

9) Control of extraction: Repeating the extraction on the extracted sample in the same conditions should give an extract of less than 2 mg; if not, use longer extraction time.


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10) Expression of result: As % of fat, with 2 decimal figures, stating which solvent was used.

100 x sample of gextract of g% Fat

11) Reference: Experimental Station for oil and fat industries (1988). Determination of fat. Method N°4. Milano, Italy.


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Extraction of oil and grease from wastewater

The method determines groups of substances with similar physical characteristics on the basis of their common solubility in carbon tetrachloride. Time ago the used solvent was a freon (trichlorotrifluoroethane) dismissed for ecological reasons. Compounds volatilized at or below 103°C will be lost when the filter is dried. The method is empirical andd reproducible results are obtained only following exactly all details.

1) Sample: 1 l of wastewater collected in a wide mouth glass bottle and immediately acidified to pH 2 or lower with hydrochloric acid (HCl) to hydrolyze soluble soaps.

2) Chemicals: Carbon tetrachloride (CCl4), reagent grade, with an evaporation residual not higher than 5 mg/l (0.005‰).

Distilled water

Diatomaceous flour filter aid suspension 10 g/l in distilled water

Boiling stones

3) Sample filtration: Prepare a 12 cm Buchner funnel with a disk of muslin cloth overlaid with a filter paper disk. Filter under vacuum 100 ml of filter aid suspension on the Buchner and wash with 1 l of distilled water. Filter acidified sample until no more water passes the filter. Transfer paper filter to a watch glass using forceps. Wipe walls and bottom of collecting bottle and Buchner funnel with pieces of filter paper soaked in solvent and add them to paper filter on watch glass. Roll the paper filter and introduce it into extraction thimble.

Dry thimble in an oven at 103°C for half an hour.

4) Extraction: 30-60 ml of solvent

Boiling stones

15 minutes with the sample immersed in solvent

30 minutes of reflux

5) Extract drying: Extraction vessel in an oven at 80°C for 15 minutes. Cool in a desiccator.

6) Weighing: The extract containing vessel with boiling stones is weighed to 0.1 mg proximation.

7) Expression of result: As mg/l with one decimal figure

8) Reference: APHA-AWWA-WPCF (1985) Standard Methods for the Examination of Water and Wastewater. 16th Ed. Washington D.C., USA.


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Extraction of oil and grease from sludges

Acidified sludge essiccated by heating gives low results. Drying is performed mixing the sludge with magnesium sulfate monohydrate which combines with water for a 75% of its weight giving the eptahydrate.

1) Sample: About 200 g of wet sludge collected in a wide mouth glass bottle. Weigh 20 ± 0.5 g of sample in a 150 ml beaker. Acidify to pH 2.0 with hydrochloric acid (HCl) to hydrolyze soluble soaps.

2) Chemicals: Carbon tetrachloride (CCl4) reagent grade with an evaporation residue not higher than 5 mg/l (0.005 ‰)

Magnesium sulfate monohydrate. Dry overnight a thin layer of heptahydrate (MgSO4 . 7 H2O) in an oven at 150°C.

3) Sample dehydration: Add 25 g of magnesium sulfate monohydrate to the acidified sample in the beaker. Stir to a smooth paste and spread on the sides of beaker. In 15-30 minutes the paste solidifies. Remove the solids and grind in a mortar. Add the powder to an extraction thimble. Wipe mortar and beaker with filter paper wetted with solvent and add to thimble.


Boiling stones



5) Extract drying: Extraction vessel in an oven at 80°C for 15 minutes. Cool in a desiccator.

6) Weighing: The extract containing vessel with boiling stones is weighed to 0.1 mg proximation.

7) Expression of results: Refer to wet solids, or dry solids if known, as mg/kg.

8) Hydrocarbons: Fatty acids as polar materials can be selectively removed by silica gel (Si02). Dissolve the residue from oil and grease extraction in 10 ml of carbon tetrachloride and pass through a small glass column (Ø 1 cm 20 cm high) filled with 30-60 mesh silica gel, only mineral oils are not retained.

9) Reference: APHA-AWWA-WPCF (1985). Standard Methods for the Examination of Water and Wastewater. 16th Ed. Washington D.C., USA.


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Extraction of petroleum source rocks

During the explorative process in search of petroleum sources special importance assumes the qualitative analysis of petroleum source rocks. In order to evaluate the petroleum potential of a particular drilling site, is carried out an analysis of hydrocarbon compounds contained in soil, clay or in crushed rock samples, coming from petroleum sources.

Usually, these tests are also performed on sea bed samples in monitoring marine pollution at various distances from the borehole.

The extraction is performed on relatively high sample amounts , because of the low content of extractable matter (usually lower than 1%).

Reasons for extraction:

-gravimetric and qualitative analysis

-sample preparation for GC-MS

1) Sample: Crush the sample and grind it (particles dimension lower than 1 mm). Weigh 15g of sample, with a tolerance margin of +/- 10mg, into an extraction thimble and put a small amount of defatted cotton wadding over the sample.

2) Chemicals: methylene chloride, reagent grade. Cotton: defatted cotton wadding.

3) Extraction: accurately weigh the glass extraction vessel with a tolerance margin of 1 mg. Add 60 ml of methylene chloride. Transfer the thimble with the sample in the extraction unit. Program, for the heating plate, a temperature of 120°C.

40 minutes with thimble immersed in boiling solvent


4) Weighing: dry the vessel containing the extract in an oven at 80°C for 15 minutes. Let cool in a desiccator up to room temperature. Weigh with a tolerance margin of 1 mg.


% extractable matter = W3 – W2 / W1 x 100

W1 = sample weight (g), W2 = glass extraction vessel weight (tare,g), W3 = glass extraction vessel weight +residue weight (g).


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Extraction of plasticizer mixtures from vinyl chloride plastics

The method is devised for the extraction of monomeric and polymeric plasticizers containing simple phtalate esters from polyvinyl chloride compositions for following gas chromatographic analysis.

1) Sample: 1 to 5 g of polymer grinded to 0.02 mm size (20 US mesh) or 5 by 5 mm squares cut from 0.6 to 2 mm thick sheets.

2) Chemicals: 2+1 mixture by volume of carbon tetrachloride (CCl4) and methanol (MetOH) both reagent grade.

Boiling chips

3) Extraction: The sample weighed to 0.1 mg proximation is placed in an extraction thimble and extracted 30 minutes immersed in boiling solvent

30 minutes under reflux washing

4) Extract drying: Extraction vessel with boiling stones in an oven at 80°C for 30 minutes

5) Weighing: The extract containing vessel with dried extract and boiling stones is weighed to 0.1 mg proximation

6) Gas chromatography: For following gas chromatographic analysis the extract is dissolved with chloroform

7) Reference: The American Society for Testing Materials (1975). Extraction and Analysis of Plasticizer Mixtures from Vinyl Chloride Plastics. ASTM Standard Practices. Philadelphia, USA.


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Extraction of rosin from paper and paperboard

The extracted matter is really colophony but in paper manufacture the term “rosin” is commonly used.

1) Sample: 5-7 g weighted to 0.01 g proximation, cut into 6x40 mm strips. Heavy paperboard can be cut into thinner layers to improve extraction

2) Sample pretreatment:: If the paper contains carbonates the sample must be immersed 5 minutes into 1 N hydrochloric acid (HCl), washed with water and dried at room temperature.

3) Chemicals: Acidified ethanol, 4 ml of concentrated hydrochloric acid (HCl) into 1 l of 95% ethanol (EtOH)

Boiling stones


Boiling stones



5) Extract drying: Extraction vessel in an oven at 105°C for 15-20 minutes

6) Weighing: The extraction vessel with the dry extract and boiling stones is weighed to 0.01 g proximation

7) Calculation:

100 x weightsample

weightvessel - weightvessel and extract rosin % =

8) Reference: TAPPI Standard T 408 05-61. Rosin in Paper and Peperboard TAPPI Standards and Suggested Methods. Technical Association of the Pulp and Paper Industry. Atlanta, Georgia, USA.


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Extraction of oils from leather

During tanning of hides to make leather, vegetable, animal and mineral oils are used to give water proofness and flexibility

1) Sample: 20 g of leather grinded to less than 1 mm size, weighed to 1 mg proximation

2) Chemicals: Petroleum ether 40-60°C or dichloromethane (CH2Cl2), reagent grade

Boiling chips

3) Sample drying: Transfer quantitatively the sample to an extraction thimble, cover with a defatted cotton plug and keep in an oven at 103°C for 2 hours


Boiling stones

30 minutes immersed in boiling solvent


5) Extract drying: Extract containing vessel with boiling chips in an oven at 103°C for 30 minutes. Let cool in a desiccator for 30 minutes.

6) Weighing: The extract containing vessel with boiling chips is weighed to 1 mg proximation.

7) Expression of results: As g/100 g with 2 decimal figures

100 x(g) weightsample

(g) wightextract esextractabl % =

8) Reference: Experimental Station for hides and tanning materials industries (1992). Leather: determination of substances extractable by dichloromethane. Neaples, Italy (in Italian). J.Soc. Leather Tech. Chem. (1965). Determination of substances soluble in dichloromethane. I.U.C./4 49,10.


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Determination of unsaponified and unsaponifiable fat in soaps

Neutral fat and unsaponifiable fat (mostly hydrocarbons) can be determined together or separated. The method considers the unsaponifiable fat not volatile at 105°C.

1) Sample: 10 to 20 g of soap weighed to 1 mg proximation is kept overnight in an oven at 105°C.

2) Chemicals: Petroleum ether 40-60°C, reagent grade. Potassium hydroxide (KOH), ethanol 1 N solution, 56 g in 1 l of 95% ethanol.

Boiling stones.

3) Sample extraction: The dry soap sample is triturated in a mortar with some washed dry silica sand and transferred quantitatively to an extraction thimble.

15 minutes immersed in boiling solvent


4) Extract drying: Extract containing vessel with boiling stones in an oven at 105°C for 30 minutes. Let cool in a desiccator for 30 minutes.

5) Weighing: The extract containing vessel with boiling stones is weighed to 1 mg proximation. The weight is due to neutral fat and unsaponifiable fat and is to be referred to the weight of sample before drying.

6) Determination of unsaponifiable fat: The extract of preceding determination is saponified directly in the extract vessel by boiling one hour with 20 ml of ethanol KOH 1 N solution. At the end the residue is dissolved with three 20 ml volumes of petroleum ether which removes the unsaponifiable fat and whose weight can be determined by evaporation in a weighed vessel.


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Extraction of ethanol soluble components from detergent formulations

Soluble components are represented by organic tensides and by sodium chloride. Also traces of other salts and raw materials, not transformed, present in synthetic tensides.

95% (V/V) ethanol does not dissolve inorganic components as sulfates, carbonates, borates, silicates, phosphates and zeolites.

1) Sample: About 5 g of formulate introduced into an extraction thimble which was previously tared in a weighing bottle together with a cotton plug.

Weigh with 0.1 mg proximation.

Dry in an oven at 105 ± 2°C.

Close the thimble with the cotton plug and introduce it into the extraction unit.

2) Chemicals: Ethanol 95% (V/V) neutralized with phenolphtalein indicator.

Boiling chips

3) Extraction: 100 ml of solvent

Boiling chips



4) Extraction drying: Extraction vessel in an oven at 105 ± 2°C for one hour or to constant weight

5) Drying of insoluble residue: Introduce the thimble with insolubilized residue in the same weighing bottle used before. Dry in an oven at 105 ± 2°C during 3 hours.

Let cool in a dessiccator and weigh with 0.1 mg proximation

6) Expression of results:

Percent of soluble components:

100 x sample of g

substances soluble of g

Percent of insoluble components:

100 x sample of g

substances insoluble of g

7) Reference: Italian norm UNI 24017 (1993). Detergents and tensides. Determination of ethanol soluble and insoluble substances (in Italian).


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Extraction of finishing oils from textiles and synthetic or natural fibres

The finishing oils used for natural and synthetic fibres provide a better crease resistance, water repellance and permanent press. They also act as lubricants for synthetic thread . Without them, high-speed commercial sewing machines could overheat. Finishing oil enhances the processability of fibres.

Reasons for sample extraction:

-gravimetric analysis

-sample preparation for GC, HPLC, etc.

1) Sample: from 2 to 10 g of thread or cloth . Cut the sample in proper size pieces.

2) Chemicals: petroleum ether 40°-60°C,analytical grade, having an evaporation residue not higher than 10 mg/l. Other suitable reagents, analytical grade: trichloro-ethylene, methylene chloride, methanol, ethanol.

3) Extraction: the sample is to be placed into the extraction thimble, weighing with a tolerance margin of 0,1mg.

60-70ml of solvent in the extraction vessels

10 min with the thimble in the boiling solvent

20 min of reflux washing

4) Extract drying: the extract containing vessel is placed in oven at 100°C for 30min. Let cool to room temperature inside a desiccator.

5) Weighing: The vessel with the dry extract is weighed with a tolerance margin of 0,1mg.


% oil = W3 – W2 / W1 x 100

W1= sample weight (g), W2 = glass extraction vessel weight (tare,g), W3 = glass extraction vessel weight+residue weight (g).


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Organic analytes extraction from soil, sediment, sludges and waste solids in preparation for GC/MS, GC o HPCL analysis

The method is applicable to the extraction and concentration of polychlorinated biphenyls (PCBs), organochlorine pesticides, nitroaromatics, hydrocarbons and chlorinated hydrocarbons, i.e. water insoluble or slightly water soluble compounds. Following the extraction steps, the samples are to be submitted to purification (clean up) by e.g. silica gel columns, before the determination of the organic analytes. Adeguate processing of samples must be adopted to avoid chronic laboratory contamination. A method blank must be included in every group of 20 (or less) samples as a control of possible laboratory contamination or interferences from extraction equipment seals and thimbles, or used chemicals.

1) Sample: 10 g dry weight. The sample surfaces should allow maximum exposure for extraction. The sample should pass completely through a 1 mm sieve. Grinding develops heat and should be performed only when non volatile organics are determined. As an alternative, cutting, shredding or any kind of breaking not developing heat can be adopted. Sample drying is also critical because a loss of volatile compounds can occur both during air drying or oven drying. The best results are obtained by mixing with anhydrous sodium sulphate (Na2SO4) until a free flowing powder is obtained (1:1 w/w or more).

2) Chemicals: -Acetone/exane mixture, 1:1 v/v, pesticide quality, for PCBs, organochlorine pesticides or semivolatile organics extraction. 50 ml per cup.

- Acetone/methylene chloride mixture, 1:1 v/v, pesticide quality, for semivolatile organics. 50 ml for each cup. - Exane, pesticide quality, for PCBs and semivolatile organics. 50-100 ml per cup. - Sodium sulfate anhydrous (Na2SO4 ), purified if necessary (interferences) by

heating 4 hours at 400°C in a shallow tray. - Boiling stones

3) Extraction: 60 minutes immersed in boiling solvent. 60 minutes under reflux washing. The recovery of solvent is interrupted when all but 2-5 ml remain in extraction cups.

4) Analysis: After cleanup the sample extract can be analyzed by gas chromotography with capillary column with electron capture detection or mass spectrometry, or by high performance liquid chromatography.

5) References: US Environmental Protection Agency (EPA) (1992). Automated Soxhlet Extraction. Method 3541. 10 ppg.

- Cibra M., Galassi S., and Mandelli A. (1996). Confronto fra i sistemi Soxhlet e Randall (Comparison between Soxhlet and Randall systems for the extraction of organic micropollutants and fats from solid matrices). In Italian. Il laboratorio 2000 – October 1996 pgg. 50-53.


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General information on the chloro-organic pesticides, on the poli-chlor-diphenils and poli-chlor-terphenils are available from: - Leoni V. and Puccetti G. (1978). Determination of pesticides containing chlorine in wastewater. Analytical methods for the analysis of waters. E-009. IRSA-CNR. Rome. - Leoni V. and Vannucchi C. (1981). Determination of poli-chlor-diphenils and poli-chlor-ter-phenils in wastewaters. Analytical methods for the analysis of water. E-011 e E-012. IRSA-CNR. Rome.


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Extraction of total fat from milk powder with a preliminary hydrolysis

1) Sample: 2 g of milk weighed in a 250 ml Erlenmeyer flask with a 1 mg proximation.

2) Chemicals: - Concentrated ammonia solution 28-30% NH3 (d. 0.89).

The hydrolysis is not performed by strong mineral acids because lactose is transformed into caramel (burnt sugar).

- Petroleum ether 40-60°C with an evaporation residue not higher than 10 mg/l.

- Boiling stones

3) Preliminary hydrolysis: Add 10 ml of distilled water to the weighed sample in the Erlenmeyer flask and stir to homogenize the suspension. Add 1.5 ml of concentrated ammonia solution and heat to 60-70°C in a water bath for 30 minutes.

4) Sample filtration: After hydrolysis the sample is filtered by a double folded paper filter soaked with water. The Erlenmeyer flask is washed by hot water, 100 ml about, and the washing is poured on the paper filter. The filter is washed with water until the filtrate is no more alkaline.

5) Filter drying: The double paper filter is placed on a watch glass and dried 2 hours in an oven at 102-105°C together with the Erlenmeyer flask used for hydrolysis. The dried filter is folded and introduced into an extraction thimble. The inner of Erlenmeyer flask and the watch glass are cleaned by a cotton swab soaked with petroleum ether, using pincers, and the swab is introduced in the extraction thimble.

6) Extraction: 60-80 ml of petroleum ether are poured into the extraction glass beaker beforehand weighed with some boiling stones with 1 mg proximation.

15 minutes with the thimble immersed into boiling solvent.


7) Extract drying: The extraction glass vessel is kept in an oven at 100°C during 30 minutes and then left to cool in a dessiccator.

8) Extract weighing: The extract containing vessel with boiling stones is weighed with 1 mg proximation.


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Determination of total fat in cheese

Water content of different kinds of cheese ranges from 30 to 60% by weight. Total fat content range is from 16 to 47% by weight. A preliminary acid hydrolysis with hydrochloric acid is aimed to free occluded or bound lipids. If this procedure is adopted follow the “determination of total fat in meat, fish, cacao and derived products” described in this manual. If the sugar content of cheese is high it is better to use an alkaline hydrolysis by ammonia to avoid charring from lactose caramelization in strongly acid medium.

1) Sample: 1-3 g of comminuted and homogenized cheese, weighed in a 100 ml tall form beaker with 1 mg proximation. 2) Chemicals: Ammonium hydroxide (NH4OH) 30%, d. 0.89, reagent grade. Distilled or deionized water. Petroleum ether 40-60°C, with an evaporation residue not higher than 10 mg/l. Boiling stones to be introduced in the extraction cup before weighing it.

3) Preliminary fat extraction: Pour 20 ml of petroleum ether on the sample in beaker. Leave 10 minutes swirling 2-3 times. Decant the petroleum ether in the corresponding extraction cup of extraction apparatus. Evaporate the residual petroleum ether placing the beaker in a boiling bath for a few minutes. 4) Sample hydrolysis: Add 3 ml of concentrated ammonia solution and 10 ml of distilled or deionized water to the beaker with sample. Place the beaker in a boiling bath for 30 minutes. Add 50 ml of hot water and filter on a double folded paper filter. Wash three times the beaker with 50-60 ml of hot water and add the washings to the double filter with hydrolyzed sample. Wash with water until no more alkaline reaction is shown by filtrate. 5) Sample drying: Place the double filter paper in a clean beaker or on a watch glass and keep it in an oven at 105°C, together with the beaker used for hydrolysis, during 1-2 hours until perfectly dry. The dry filters are folded and introduced into an extraction thimble. The internal of the beaker or watch glass used during drying and of the beaker used for hydrolysis are cleaned with cotton plugs soaked in solvent, using forceps. The plugs are added on top of filters in the thimble. 6) Extraction: 40-50 ml of petroleum ether are added to the volume used for preliminary fat extraction and just present in the extraction cup. Some boiling chips were added to the cup before weighing it. Thimble and cup are placed in position. 20 minutes with thimble immersed in boiling solvent 40 minutes of reflux washing 7) Weighing: The extract containing cup with boiling stones, after complete evaporation of solvent, is weighed to 1 mg proximation. 8) Expression of result: Refer to wet sample weight and give the result as fat g/100 g with one decimal figure.


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Determination of total fat in flour, bread, bakery products and pasta with preliminary acid hydrolisis

The total fat content of this group of products ranges from 1% in refined wheat flour, plain wheat bread and pasta without eggs, to 3% about in egg noodles, up to 4-5% and more in biscuits and other bakery products. Some lipids are occluded or bound to other components and thus a total fat determination is obtained only after preliminary acid hydrolysis. 1) Sample: 2 to 10 g of grinded and homogenized matter weighed in a 250 ml Erlenmeyer flask, which can be connected to a reflux condenser, with 1 mg proximation. 2) Chemicals: Hydrochloric acid (HCl) about 8 N, 100 ml of concentrated hydrochloric acid, reagent grade, d. 1.19, mixed with 50 ml of water. - Hexane or petroleum ether 40-60°C with an evaporation residue not higher than 10 mg/l. - Ethanol (C2H5OH) 95% v/v - Boiling stones 3) Sample hydrolysis: add 1 ml of ethanol for each gram of sample in the Erlenmeyer flask to prevent the formation of lumps after acid addition. Stir to moisten all particles. Add 5 ml of 8 N hydrochloric acid for each gram of sample in the Erlenmeyer flask. Mix well acid after assembling the reflux condenser set the flask in a water bath held at 70-80°C for 30-40 minutes stirring at intervals. Remove from water bath and remove the condenser. Add 100 ml of hot water and filter on a double folded paper filter. Wash three times the Erlenmeyer flask with 60-70 ml of hot water and add the washings to the double filter with hydrolized sample. Wash with water until no more acid reaction is shown by the filtrate. 4) Sample drying: Place the double filter paper in a 300 ml beaker and place 1-2 hours in an oven at 103°C, together with the Erlenmeyer flask used for the hydrolysis. The dry filters are rolled and introduced in an extraction thimble. The internal of Erlenmeyer flask and beaker are cleaned with a cotton plug soaked in solvent, using forceps. The plug is added to thimble 5) Extraction: 30-60 ml of the chosen solvent Boiling chips 30 minutes with thimble immersed in boiling solvent 60 minutes of reflux washing 6) Extract drying: Extraction vessel with boiling stones in an oven at 103°C for 30 minutes. Cool in a desiccator. 7) Weighing: The extract containing vessel with boiling stones is weighed to 1 mg proximation. 8) Expression of result: Refer to wet sample as weighed and give the result as fat g/100 g with one decimal figure 9) Reference: AOAC Official Methods of analysis n° 920.39.B


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Determination of oil content in fried potatoes

Fat content of crude potatoes is very low, 0,1% by weight with a moisture of 80% about. The high absorbing capacity of starch gives a fat (oil) content up to 40% in fried potatoes while the water content can be lowered to only 2-4% in thinly sliced potatoes.

1) Sample: 5 g of product grinded and sieved by US-ASTM mesh 8 (2.36 mm) and then by US-ASTM mesh 20 (0.75 mm) to remove fines. The sample is weighed to 1 mg proximation in a glass beaker. Then 1.5-2 g of anhydrous sodium sulfate (Na2SO4) are added and mixed to the sample to retain moisture. If the moisture content of sample is higher than 4% a higher amount of sodium sulfate should be added.

2) Chemicals: : Petroleum ether, 40-60°C, reagent grade with an evaporation residue not higher than 10 mg/l. - Sodium sulfate (Na2SO4), anhydrous. Boiling stones. 3) Extraction: The sample with sodium sulfate is introduced in an extraction thimble. The glass beaker used for weighing is cleaned by a cotton plug soaked in solvent, using forceps. The plug is added on top of sample in thimble. 80 ml of petroleum ether are added to each extraction glass beaker preweighed with some boiling stones to 1 mg proximation. 15 minutes with thimble immersed in boiling solvent 30 minutes of reflux washing

4) Weighing: After solvent recovery the glass beakers with extract and boiling stones are placed in an oven at 103°C for 30 minutes to remove the last traces of solvent. The beakers are then cooled in a dessicator and weighed to 1 mg proximation. 5) Expression of result:

100xSW

T1T2fat% −=

T1 = weight of beaker before extraction T2 = weight of beaker after extraction SW = sample weight

6) Reference: Francesca De Vecchi – DISTAM – Univ. of Milan – “Estrazione di grassi da matrici solide” in Italian – Il laboratorio 2000 – Novembre 1998 page 58


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Determination of the fat content in animal feed

The method is to be used for the crude fat determination in the sample.

1) Sample: 3 g of product , grinded to 1mm size about, weighed with a tolerance margin of 1mg and introduced into an extraction thimble.

2) Chemicals: Petroleum ether, 40-60°C, reagent grade with an evaporation residue not higher than 10 mg/l. 3) Extraction: 60ml of solvent introduced into the glass vessel, preliminarily weighed with a tolerance margin of 1mg. 30 minutes with thimble immersed in boiling solvent 60 minutes of reflux washing 4) Weighing: After the solvent recovery, the glass extraction vessels with the extract are placed in an oven at 105°C for 30 minutes to remove the last traces of solvent. The vessels are then cooled in a desiccator to room temperature and weighed with a tolerance margin of 1 mg.

5) Expression of the result:

% fat = T2 – T1 / SW X 100

T1 = weight of vessel before extraction (g)

T2 = weight of vessel after extraction (g)

SW = sample weight (g)

6) Reference: AOAC. Official Methods of Analysis (1990) 15th Ed. 3rd supplement 1992. Arlington, Virginia, USA, method 920.39.


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Determination of the total fat content in dry animal feed

This method is to be used to determine the total crude fat content of the product.

1) Sample: 3-4g of sample as is, ground to about 1mm size, weighed with a tolerance margin of 1 mg into a 250ml Erlenmeyer flask provided with a reflux condenser.

2) Chemicals: hydrochloric acid (HCl) about 4N, 100ml of concentrated hydrochloric acid, d 1.19, mixed with 200ml of water. Diatomaceous powder as a filtration aid. Petroleum ether, 40-60°C, with an evaporation residue not higher than 10mg/l. 3) Sample hydrolysis: pour 50ml of HCl 4N into the Erlenmeyer flask containing the sample. After assembling the water cooled reflux condenser, the flask with the acidified sample is heated at boiling temperature 1 hour long. At the end of the hydrolysis 150ml of deionized or distilled water and 1g of diatomaceous powder are added to the sample still hot. 4) Sample filtration: a double paper filter water soaked is used to filter the hydrolyzed sample. The Erlenmeyer flask used for the hydrolysis is washed with hot water and the washings are poured on the filter. Wash with water until the washings do not show acid reaction to turmeric indicator paper. 5) Sample drying: the double paper filter is placed on a watch glass and dried in oven at 102°C for 2 hours together with the flask used for the hydrolysis. The dry filters are rolled and introduced into an extraction thimble. The internal side of the flask and watch glass are wiped with some filter paper solvent soaked, which is then introduced in the thimble as well. Use forceps. 6) Extraction: 60ml of solvent poured into the glass extraction vessel, previously weighed with a tolerance margin of 1mg. 15 min with the thimble dipped in the boiling solvent 30 min of reflux washing 7) Weighing: after the solvent recovery, the glass extraction vessels containing the extract are to be placed in oven at 105°C for 30 min, in order to eliminate traces of solvent. Then the vessels are cooled down to room temperature inside a desiccator and finally weighed with a tolerance margin of 1 mg.


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% fat = W2 – W1 / SW X 100

W1 = extraction vessel weight before the extraction (g, tare)

W2 = extraction vessel weight after the extraction (g)

SW = sample weight (g)

9) Reference:

AOAC. Official Methods of Analysis. Arlington, Virginia, USA, method 7.063.


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Declaration of compliance

We manufacturer VELP SCIENTIFICA s.r.l. address Via Stazione, 16 USMATE (MI) Italy Under our responsability declare that the product is in according with the following standards: EN 61010-1/2001 EN 61326-1/2000 And satisfies the essential requirements of directives: Machines directive 98/37/CEE Low voltage directive 2006/95/EC Electromagnetic compatibility directive 2004/108/EC Plus modifications and that the documents listed in the annex V are available at Velp's offices as per the machine directive.


10001364/A11

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