hazelnut shell lignin extraction and characterization Ïu azogue coll 2nd phd in chemical...
TRANSCRIPT
Hazelnut shell lignin
Extractionand
characterization
Ïu Azogue Coll
2nd PhD in Chemical Engineering
Summary
• Introduction about lignin
• Research objectives
• Results and conclusions about investigation
What is lignin?
• Vegetable material– Cellulose– Hemicellulose– LIGNIN
• Water removal from sugars to create aromatic structures
• Functions– Strength of wood
Where we can find?
• Lignin is an integral part of the secondary cell walls (not all cells)
• The most abundant organic material on earth after cellulose
• Most quantities of lignin– Hard parts of plants (Fruit shells, trunk)– Organic material from ground
Composition and structure
• Complex three-dimensional structure– Quantity increase through plant life– Intracellular growth
• Natural lignin composition and structure are unknown
• Factors which affect composition– Plant species– Part of plant
Composition and structure
• Three principal monomers– p-coumaryl alcohol– Coniferyl alcohol– Sinapyl alcohol
Natural and industrial sources
• Natural sources– All vegetable material
• Industrial sources– Pulping industry
Millions of tones are “produced” in paper industry
Production
• Paper production– Cellulose from vegetable material– Lignin is strongly linked to cellulose
• Industrial pulping allow cellulose and lignin separation– Pulp: To produce paper– Black liquor: Non-cellulose components
(Lignin)
Lignin: State of art
• Nowadays lignin is used as:– Binder– Dispersant– Emulsifer– Sequestrant
• Many researches are looking for new viable applications– EUROLIGNIN. European project to study
lignin properties, characterization, uses...
Research objectives
• Obtain optimal extraction conditions– Extractor agent– Temperature– Time
• Characterization– Functional groups
• Applications– Chelating agent
Extraction methods. Pulping
• Pulping process reproduced in laboratory:– Extractor agent (Soda, ethanol...)– Black liquor is separated by centrifugation
• Acid-precipitation of lignin from black liquor
• Lignin centrifugation and washing
Autoclave
Delignificated fiber
Black liquor
Fiber + Extractor agent solution
Centrifuge
Lignin precipitation with acid
Centrifuge
Liquid phase
Wet lignin
Dry lignin
Dryer
Characterization
• Principal polymer characteristic:– Conformation– Configuration– FUNCTIONAL GROUPS
• Methods:– Potentiometric– Spectroscopic
Potentiometric method
• Lignin titration– Obtaining of potentiometric curve– Observe equivalent point– Calculate functional group quantity
Spectroscopic method
• Different techniques– Fourier Transform Infrared– Ultraviolet– Nuclear magnetic resonance
• Analyzing the spectra diagrams:– Functional groups– Comparison between different lignins
Applications
• Chelating agent– Toxic metals complexationPb, Cr...– Metal micronutrients complexationNi, Mg, Fe, Zn...
• Complexation curves– Highest absorption
• Study optimal conditions– pH– Temperature
Results and conclusions
• Hazelnut lignin extraction depends mainly of soda concentration in present conditions
• Potentiometric titration require much experimentation time but can be a good characterization method
•That’s all!• Thank you very much for
your attention
• If you want to ask questions about presentation this is the moment (short moment I hope...)
Potentiometric curve
Functional groups
Carboxylic group
Phenolic hydroxyl group
Hydroxyl group
Lignin extraction
6% 9% 1215
30 min
60 min0,05,0
10,015,020,025,030,035,040,045,0
Lig
nin
e
xtr
ac
tio
n (
%)
NaOH concentration %
Extraction at 130ºC