School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Pretreatment of different materials: An international perspective Mohammad J. Taherzadeh School of Engineering University of Borås

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery A variety of lignocelluloses are attractive in different reagions!

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Complex plants cell walls

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery A challenge by lignin and hemicellulose! Lignin Hemicellulose Cellulose chains

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Challenge of crystallinity!

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Alternative patterns of aggregation A.The fibrils were twisted individually and then the assembly also twisted. B.The individual fibrils were twisted of 90°over 300 nm and then packed as closely as possible C.The fibrils were collectively subjected to twist. Helical form of a 6 by 6 nm nanofibrils is compared with that of nine 2 by 2 helical nanofibrils packed as close as possible, with the same period.

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Alternative patterns of aggregation Would not be mechanically stable Cellulose is deposited alone The most efficient load-bearing structure

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Changes during Isolation Two stages in isolation will influence the final pattern of aggregation: 1. Elevation of temperature 2. Effect of drying

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery  Cellulose is hydrated in its native state at the level of elementary nanofibril Effects of elevated temperature Temperature elevation changes the state of aggregation of native cellulose.

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Drying results in distortion of nanofibrils by: Removing too much of the water needed to lubricate the motion of the nanofibrils relative to each other. Drying?

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Linear parallel segments, which are artifacts of isolation processes are easily mistaken for naturally accuring crystalline domains. Changes during Isolation

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Pretreatment in order to: Release cellulose from the structure: Remove or hydrolyze hemicelluloses Remove lignin Reduce cellulose crystallinity Provide enough accessible surface area to absorb the enzymes Adsorption/desorption rates of the enzymes Remove inhibitory compounds following the substrate

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Pretreatment methods (various efficiency on different factors) Physical methodsChemical & PhysicochemicalsBiological milling: - Ball milling - Two-roll milling - Hammer milling - Colloid milling - Vibro energy milling irradiation: - Gamma-ray irradiation - Electron-beam irradiation - Microwave irradiation Others: - Hydrothermal - High pressure steaming - Expansion - Extrusion - Pyrolysis Explosion: - Steam, Ammonia, CO 2, SO 2, Acids Alkali: - NaOH, NH3, (NH4)2SO3 Acid: - Sulfuric, Hydrochloric & Phosphoric acids Gas: - ClO2, NO2, SO2 Oxidizing agents: - Hydrogen peroxide - Wet oxidation - Ozone Solvent extraction of lignin: - Ethanol-water extraction - Benzene-water extraction - Ethylene glycol extraction - Butanol-water extraction - Swelling agents Organosolvs/ Ionic liquids Fungi and actinomycetes (lignin peroxidase, manganese peroxidase, laccase…)

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Cellulose solvents effective for crystallinity

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Possible non-aqueuous cellulose solvents

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Low-temperature Ionic Liquids ( C) 1-Ethyl-3-methylimidazolium acetate [EMIM]OAc 1-Ethyl-3-methylimidazolium chloride [EMIM]Cl 1-Allyl-3-methylimidazolium chloride [AMIM]Cl 1-Butyl-3-methylimidazolium chloride [BMIM]Cl 1-Butyl-3-methylimidazolium bromide [BMIM]Br 1-Butyl-3-methylimidazolium acetate [BMIM]OAc 1-Butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF4 1-Butyl-3-methylimidazolium hexafluorophophate [BMIM]PF6 1-Butyl-3-methylimidazolium methylsulfate [BMIM]MeSO4 1-Octyl-3-methylimidazolium chloride [OMIM]Cl Imidazole salts

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Milling: Usually part of the process!  Milling:  Ball milling  Two-roll milling  Hammer milling  Colloid milling  Vibro energy milling  Functions:  Size reduction  Degree of crystallinity  High energy costs!

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Irradiations  Irradiation: –Gamma-ray irradiation –Electron-beam irradiation –Microwave irradiation  Usually good results  Expensive!  Ultrasound might have a good a chance for commercialization (already in the market)

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Hydrothermal process  Cooking in liquid hot water generally at °C  Water under high pressure can: – Penetrate into the biomass, –Hydrate cellulose, –Remove hemicellulose (a major function), –Remove part of lignin (but not so effective),  Autohydrolysis occur due to releasing some carboxylic acids such as acetic acid,  Advantages: –No addition of chemicals, –No neutralization afterward, –No corrosion-resistant materials for reactor, –Could be combined with e.g. a delignification process  Industrial application such as by Danish Inbicon

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery High-pressure steaming (+explosion)  Cooking with steam generally at °C & min  If followed by explosive releasing of the pressure = Steam explosion  Steam explosion is one of the most popular pretreatments  Explosion has important function  pH reduces due to autohydrolysis  Industrtial applications by e.g. –Cambi (Norway) –Chemtex (Italy) –Greenfield (Canada)

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Dilute-acid processes!  Similar methods in pulp industries  Similar temperature/Pressure as steam explosion!  Improvement by addition of: –Dilute-acid (0.1-1% acids: H2SO4, HCl, etc.) –Carboxylic acids (e.g. acetic acid) –1-4% SO2 –CO2  Functions: –Open up the polymers –Hydrolysis of hemicellulose  Potential commercialization by e.g : –POET (USA) –SEKAB (Sweden) –ABENGOA (USA)

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Alkaline cooking!  Treatment with alkaline solutions: –NaOH, –Ca(OH) 2 (lime) or –Ammonia (AFEX)  Popular in pulp industries (kraft process)  To remove lignin effectively (+ sometimes a part of the hemicellulose)  To reduce crystallinity of cellulose  Generally at about C for a few minutes to hours  High pH (e.g ) or alkali concentrations 1-20%  High amount of NH3 is needed (e.g. 1:1 kg/kg NH3/biomass)  Can also be used with explosion

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Oxygen treatments (wet oxidation)!  Wet oxidation = treatment with water and air or O2 at C for e.g. 30 min.  It is exothermic process (because of oxidations)  It is a combination of solubilization and degradation reactions  Hydrolytic reactions  organic acids  The hemicelluloses are extensively cleaved to monomeric sugars;  The lignins undergo both cleavage and oxidation;  Cellulose is partly degraded.

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Organosolves/Ionic liquids!  Lignocelluloses are mixed with organic liquid (and water?) and heated to dissolve: –Ligning –And/or cellulose  Temperatures of °C can be used: –Depends on the solvent used!  Simple solvents such as ethanol or acetone can be used!  Low Temperature Ionic Liquids are hot research topic today!

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Our latest results for high crystalline cellulose!  N -Methylmorpholine- N -oxide (NMO or NMMO)  No toxicity  Solvent of cellulose  Industrial solvent  C

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Conclusion  Lignocelluloses are diffent:  Type,  Age,  Crystallinity  Dryness,  Type of the cell wall  ….  Pretreatments have different effectivities on various lignocelluloses,  Great developments in pretreatments, but still long way to go…

School of Engineering Mohammad. hb. se Mohammad. hb. se Tel : Tel : www. hb. se / ih / resourcerecovery Thank you! Question?