Biodiesel in the Classroom

Barry Latham, M.A.Ed., B.S.Chemistry & Physics

InstructorBloom High School

Chicago Heights, Illinois

Funding Information

• A+ for Energy $40,000 awarded for 2007-2010 by BP, Inc.– Biodiesel, Photovoltaic Power, Fuel Cell, Wind, Efficiency projects– Ethanol Research, Alternative Energy Fairs

• $1,450 awarded 2006-2008 by Bloom Foundation– Analytical balances for research lab– Supplemented purchase 6.5kW (bio)diesel generator– Momentum carts for physics course

• $3,500 Earth Day Network awarded October 2008– Field trip to Eco-House at Museum of Science & Industry– 1982 Mercedes Benz 300SD Turbo Diesel

• $5,000 DonorsChoose.com awarded April-December 2008– Digital Video camera, Molecular models, LCD Projector– Model rockets, Soap making supplies

Biodiesel Terminology, 1

• Biodiesel- fuel made from vegetable oils or animal fats– Transesterification (veg oils)- the process of

exchanging an alkoxy group of an ester compound with another alcohol

– Saponification (animal fats)- the hydrolysis of an ester under basic conditions to form an alcohol and the salt of the carboxylic acid

• Alcohol- any carbon chain which includes an –OH group– Methanol (MeOH)– Ethanol (EtOH)

Biodiesel Terminology, 2

• Catalyst- a substance that is used in a chemical reaction, but not consumed– Potassium Hydroxide (KOH)– Sodium Hydroxide (NaOH)

• FAME- Fatty Acid Methyl Esters (<1 g/mL)– Biodiesel

• B100- 100% biodiesel• B20- 20% biodiesel, 80% traditional diesel• Glycerin- co-product of biodiesel (~1.173

g/mL)– Can be made into liquid (KOH) or bar (NaOH) soap

Vegetable Oil Sources

• In the U.S., most biodiesel is made from soybean oil or recycled cooking oils– Typically collected as waste oil from restaurants– Restaurants pay to have it removed, but you remove

it for free: everybody wins!– Times are changing, though, and waste oil is getting

expensive (regionally dependent)

• Animals fats, other vegetable oils, and other recycled oils can also be used to produce biodiesel

• Blends of all kinds of fats and oils may be used to produce biodiesel

Catalyst Choice

• Potassium Hydroxide (KOH)– Most used by homebrewers– Dissolves faster as flakes than NaOH pellets– Glycerin produced can be easily made into liquid soap

• Sodium Hydroxide (NaOH)– Typically causes more complications with soap formation– Used more in the industry– Glycerin produced can be easily made into bar soap

• Both have a high pH (caustic)• Both are dangerous- can burn skin, eyes, respiratory

system

Alcohol Choice• Methanol (MeOH)

– Shortest-chain alcohol– Most used by both homebrewers and in the industry– Biological effects similar to consuming ethanol, but more

severe• Can cause nervous system failure, blindness if ingested or

absorbed through the skin or breathed in great quantities

• Ethanol– 2-carbon chain alcohol– More restrictions on purchasing, storage and use– Higher rate of complications in reaction– Can cause inebriation

• Both highly flammable and must be respected• Store only as much as you need in a safe area

– Obey local fire codes

Safety Issues• Methanol

– Flammable– Can be absorbed through the

skin– Can cause blindness and death

• Potassium Hydroxide– Burns– Do not allow to touch your skin

• Personal Protection Equipment (PPE)– Operate in a well-ventilated area– Wear safety goggles– Protective gloves– Do not directly inhale any

vapors– Tie lose hair back– Wear closed toe shoes and long

pants

Oil Titration• Used to measure the amount of Free Fatty Acids in

used or virgin oil– Higher titration is less desired, but still usable– More FFA’s mean more catalyst needed means more expense

• Performed to check quality of oil– Can be performed at oil collection site– Use disposable syringes and small plastic, re-sealable

containers

• Indicator Choices– Phenolphthalein, Phenol Red, pH Meter, Tumeric spice– Looking for color change (near pH 7.0)

Water Testing

• When using used oil, it MUST be water-free to react properly– Qualitative Heating Test (Crackle test)– Centrifuge Test

Crackle Test

• When heated over a hotplate, water will “crackle” in the pan, indicating its presence

• Heat a cup of oil to ~100°C

• If the oil sputters, then water is present– More sputtering = more water

• Water will have to be removed by heating or settling over time and tested again

Centrifuge Test

• Oil and water will separate over time• Centrifuging will speed up this process

• Fill two appropriate sized test tubes ¾ of the way with your used oil

• Spin for 5 minutes• The oil will rise to the top and water will

settle to the bottom• The presence of water indicates that

your oil will need to be treated further– Heating– Settling

Dewatering

• Water in your used oil will complicate the formation of biodiesel and must be removed

• Heating

• Settling

Heating to Dewater

• A band heater on a 55-gallon drum will heat your oil sufficiently– Shorter time period (hours-days?)– Consumes electricity

• Use gentle agitation– Emersion mixer set on low setting– Stir once or twice a day

Settling to Dewater

• Allowing a 55-gallon drum filled with used oil will settle your water to the bottom and can be drained off– Much longer time

period (weeks?)– Consumes no

electricity

• Avoid any agitation

FAME Equation“Fatty Acid Methyl Ester”

Incomplete Reactions

                            

                              

                           

                                 

                          

                                     

monoglyceride(2/3 reaction)

diglyceride(1/3 reaction)

Triglyceride(no reaction)

“Dr. Pepper” MethodSingle-Stage Process

• Is typically used before a large batch

• Results indicate how well the method will work on this specific oil

• Must be done in the lab, not at oil collection site

• Takes 12-24 hours for results

• Performed in plastic pop bottle– MeOH will start to eat plastic after 24-

36 hours

Appleseed Processor

• Plumbing w/ Pump ~$550• 120V Water Heater

~$400• Lumber ~$25

• No plumbing experience needed

• All new parts used• Costs can be reduced by

salvaging/recycling

Reactor Specifics

• Water heater preferred over steel drum– Pre-insulated– Pre-plumbed– Pre-wired for heating elements

• Electrical water heater has less risk of explosion hazard– Internal immersion heaters– Upper heater disabled; it is rarely submerged

• Needs to be connected to 120VAC source– Electrical box & switch needs to be installed

• Do not compromise temperature regulators– Explosion risk

Reactor Assembly

• Clear instructions– Easy for students to

assemble

• New water heater used– No internal calcium

scaling– Not inheriting other

people’s problems

Cheap Schematic

16%BOOST Method100L, 16% MeOH, 2-Stage Process

• Perform titration– Our oil titrates at 0.44 (August 28, 2008, 34 trials)– 0.45 (March 27, 2009, 5 trials)

• Add 89% of KOH needed into 16L MeOH– Mix thoroughly (will mix overnight)

• Add 14L of mixture to heated oil (55°C)• Circulate for 1 hr. and settle overnight• Add remaining KOH to remaining KOH/MeOH• Drain glycerin and add remaining KOH/MeOH

mixture• Circulate for 3 hr. and settle overnight• Drain glycerin

80/20 Method100L, 18% MeOH, 2-Stage Process

• Perform titration– Our oil titrates at 0.44 (August 28, 2008, 34

trials)• Add all KOH needed into 18L MeOH

– Mix thoroughly (will mix overnight)• Add 14.4L of mixture to heated oil (55°C)• Circulate for 1 hr. and settle overnight• Drain glycerin and add remaining

KOH/MeOH mixture• Circulate for 3 hr. and settle overnight• Drain glycerin

22% Method100L, 22% MeOH, Single-Stage Process

• Perform titration– Our oil titrates at 0.44 (August 28, 2008,

34 trials)

• Add all KOH needed into 22L MeOH– Mix thoroughly (will mix overnight)

• Add all of the mixture to heated oil (55°C)

• Circulate for 3 hr. and settle overnight• Drain glycerin

Methods Summary• %MeOH needs to be at least 13%

– More MeOH ensure greater completion of reaction– Too much can be wasteful, though

• Circulation times can vary– 1-3 hours per batch seems to work for most

• Batch sizes of 100L used for simplicity in calculations (scaling up or down)

Glycerin Removal

• Drain the bottom layer of glycerin

• Dr. Pepper Method– Invert pop bottle and

gently squeeze while using your thumb as a valve

• It is better to overflow and lose some biodiesel, than to leave some glycerin in your biodiesel

Biodiesel Size Exclusion Chromatography

• Only B100 remains after final glycerin drain– Longer wait-time allows more glycerin to settle out

• Residual MeOH may remain– Costly/complicated to distill MeOH out of glycerin

• B100 pumped through molecular sieve into storage drum– 4A sieve traps small molecules (MeOH, H2O) and allows larger

molecules (biodiesel, glycerin) to pass– Sized-based trap– Based on gas trap designs and drying agents

• Because MeOH exists at ppm or ppb levels, sieve may take a very long time to exhaust– No current research available– Can be recharged by heating in an exhaust hood or outside

• To vaporize MeOH and “bake-off” biodiesel adhered to surface

Custom SECDry-washing System

Water Washing (optional)• Mist washing- a fine mist of water onto

surface of biodiesel– Water needs to be small droplets and hit

the surface at a low velocity

• Drain water as misting continues– Water droplets pick up impurities on their

way through the biodiesel

• Fuel will eventually get clear as water drains out

• Turn off water and allow the fuel to settle

• Water is a contaminant in biodiesel and is sometimes difficult to remove

Bubble Washing (optional)• Gently add 1 part water to 2-3 parts biodiesel• Add an aquarium air stone with air pump

– Can use copper tubing with pin-sized holes drilled all over

• Bubble air through the water• Batch-based, not continuous flow

• Air bubbles allow indirect agitation of the two fluids

• Tiny amounts of water picked up and carried through the biodiesel, picking up contaminants

• Bubble bursts at the surface and drops the water, which picks up more of the soaps and contaminants on it’s way back down

• After about 6 hours of this ‘washing’, the air is stopped, water is drained, more fresh water is added, and the process repeats

• Repeated 3 times until the water measures the same pH of your tap water and is perfectly clear

• Still water-based washing

Waste Water Disposal

• When water-washing, the water needs to be disposed of

• Treat with a mild acid until neutralized– Acids- vinegar, citric acid, ascorbic acid– Use pH indicator from titration– Neutralized water can be safely dumped down the drain

• Creates lots of waste, depending on how you water wash

• Tests performed August 2008 indicated that although the biodiesel does appear clearer after water-washing, it passes the 3/27 test without it

Emulsions

• Emulsions are a mixture that occur when a water layer and an oil layer refuse to separate

• Can occur during the water-wash phase– Cause- aggressive washing– Biodiesel becomes "imprisoned"

in soap spheres– Relating to un-reacted oils,

poorly separated biodiesel/by-product, etc.

Emulsion Corrections

• Soap spheres can be broken apart– Freezing the whole emulsion– Lowering the surface tension

using a solvent like alcohol– The alcohols (methanol in

glycerin) are a readily available solvent

• Much easier than freezing a large emulsion solid.

– Drawback- Expensive to freeze 55 gallons

• Heating batch to 50-60°C– Expensive to heat 55 gallons

• Adding ordinary table-salt, sodium chloride can work– Dilute the salt in water first– Salt is an impurity that you

should be washing out instead of washing in

– Adds halogens to water supply

• An acid-quench will also break an emulsion or prevent it forming– Might disguise a processing

problem that the emulsion would reveal

– Always do a wash-test first

Quality Testing3/27 Test

• Tests for triglycerides (unreacted oil)

– Does not for monoglycerides and diglycerides

• Tells you if you must reprocess

• Add 1 part biodiesel to 9 parts methanol in a sealable vial (3mL & 27mL, etc.)

– Be very precise with measurements if using these small amounts

• Look for particles in the vial and/or cloudiness

– If present, your sample failed- reprocess

• Sample should be clear to pass

Biodiesel Storage

• Biodegradable in months to years– Less time than table sugar– No research to support this claim

• Only make as much as is needed• Hydroscopic (attracts atmospheric

water)• More glycerin falls out over time,

regardless of draining or filtering• Fire code regulations

Biodiesel UsesBeyond Diesel Vehicles

– a corrosion preventative

– a parts cleaner and degreaser

– a graffiti remover– a paint and resin

cleanup– a hand cleaner– a crop adjuvant– a metal working

lubricant– a screen printing

ink remover– aircraft fuel– home heating oil

– a lubricity additive for diesel fuel

– an adhesive remover

– a mold release agent

– an asphalt cleanup agent

– an oil spill cleanup and bioremediation agent

– an auto wax remover

Biodiesel Use Cautions

• Biodiesel as an excellent solvent– All natural rubber will eventually be dissolved

• Use Viton, or other synthetic rubber hoses, seals and gaskets

– Breaks down petroleum “grit” that builds up over time in the combustion chamber

• Grit is dissolved by biodiesel and can clog fuel and exhaust filters

– Starting with a lower % of biodiesel slows this process• Can increase % over time while replacing rubber material

and filters

Benefits of Biodiesel

• Operates in conventional diesel engines

• Does not require special storage• Exhaust is less offensive

– Smells like food that it was used for

• Safer to use than dino-diesel• Reduced greenhouse gases

emissions– 30-80%, depending on %B

• Improves domestic energy security

Closed-Carbon Cycle

Glycerin TreatmentMeOH Removal

• MeOH is still present and needs to be removed before it can be used– NOT a co-product, just used in excess– Common misconception that MeOH is produced

• Distillation- separation of liquids based on boiling points– MeOH has a lower boiling point than glycerin

• Turns to vapor first• Can be condensed, collected and reused

– Glycerin turns thicker and darker– Heating element, not flame, is used

Glycerin Co-ProductSoap (1L batch)

• Remove the residual (toxic) methanol first

• KOH-based biodiesel makes liquid soap glycerin– NaOH-based production makes

bar soap

• At 50°C, preheat any of the following ratios before mixing for 5 minutes– Glycerin 33mL 47mL 54mL– Water 7mL 5mL 5mL– KOH 1g 1g 1g

– Can not use KOH and NaOH inter-changeably

• Fragrances and dyes can be added– D-limonene smells like oranges and is

cheaply made/purchased– Most dyes muddy the dark brown

color

Glycerin Co-ProductOther Uses

• Health supplement– Increases blood volume– Enhances temperature regulation– Improves exercise performance in the heat– Helps "hyperhydrate" the body by increasing blood volume

levels and helping to delay dehydration

• Other uses– Glycerine is also a source of lecithin

• fat emulsifier and a vital component of all cell membranes in the body

– Tocopherol (vitamin E)– Skin moisturizer, lotion, deodorant, makeup, toothpaste,

sweets and cakes, pharmaceuticals and patent medicines, paper manufacturing, printing ink, textiles, plastics, and electronic components

Glycerin Co-ProductOther Uses

• Paint brush cleaner– Rinse brush as much as possible with water – Work brush in a small container with about 20 mL of

glycerin– Rinse brush under water until all milky-ness is removed– Repeat glycerin stage with fresh glycerin as needed– Check that brush doesn't smell of paint and store brush as

usual.

• Safe sweetener:– Glycerin is an alcohol and is used as a preservative– It is very sweet, yet it contains no sugar– This makes it an ideal sweetener for patients who cannot

take sugar

Cross-Curricular Opportunitiesfor Biodiesel & Soap

• Art Class– Dispensing Container Design– Brand name & Label graphics

• Economics– Cost Analysis of Biodiesel & Glycerin Soap– Marketing of product

• Fundraiser

Web Resources• blatham.multiply.com

– Personal biodiesel website• www.localb100.com

– For small scale producers• utahbiodieselsupply.com

– Produce, Promote and use Biodiesel

• journeytoforever.org/biodiesel.html– Information & tutorials

• www.biodiesel.org– National Biodiesel Board

• www.spill911.com– Safety, Spill Containment &

Industrial Supply• www.mcmaster.com

– Industrial equipment

• www.globalindustrial.com– Material Handling Equipment

• www.bloomhs.org– Bloom High School, Chicago

Heights, IL• www.biodieselcommunity.org

– Collaborative Biodiesel Tutorial

• www.ucsusa.org– Union of Concerned Scientists

• BiodieselAmerica.org– Resources, Information,

Community & News• www.B100Supply.com

– Appleseed Reactor• www.graingercom

– Industrial equipment

Grants, 1• A+ for Energy

– www.aplusforenergy.com

• Earth Day Network– www.earthday.net

• Donors Choose– www.donorschoose.com

• American Honda Foundation– corporate.honda.com/america/philanthropy.aspx?id=philanthropy_overview

• National Science Teachers Association– www.nsta.org/academy/2009/FellowApplication.aspx

• Bristol-Meyers Squibb– www.bms.com/responsibility/grantsandgiving/medical_science_education/

Pages/default.aspx

Grants, 2• Motorola Enterprises Mobility Business and Symbol Technologies

– www.symbol.com/category.php/?category=736

• Toshiba– www.toshiba.com/tafpub/upload/page/100045/25964_Executive.pdf

• The Charles A. and Anne Morrow Lindbergh Foundation – www.lindberghfoundation.org/grants/index.php

• Albertson’s– www.albertsons.com/abs_inthecommunity/

• Green School Project– greenschoolproject.com/default.aspx

• Jewel-Osco– www.jewelosco.com/eCommerceWeb/CommunityAction.do?

action=beginCommunity