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BERG lignin seminar Analytical (PY-GC-MS) pyrolysis of lignin. Daniel J. Nowakowski. Lignin chemistry.
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BERG lignin seminar Analytical (PY-GC-MS) pyrolysis of lignin Daniel J. Nowakowski
Lignin chemistry Lignin is usually considered as a polyphenolic material having an amorphous structure, which arises from an enzyme-initiated dehydrogenative polymerisation of coniferyl (a), sinapyl (b) andtrans-p-coumaryl (c)alcohols. Structure of plant cell wall BioEnergy Research Group seminar 17th September 2007 2/9
Lignin chemistry Dimmers and trimeres structures of lignin with the main types of linkages connecting phenylpropane units BioEnergy Research Group seminar 17th September 2007 3/9
PY-GC-MS analysis of Organosolv lignin [commercially available lignin] Main degradation productsof Organosolv lignin:- 1,2,3-trimethoxybenzene- 2,6-dimethoxy phenol- 2-methoxy-4-methyl phenol- 2-methoxy phenol- furanaldehyde and carboxfuranaldehyse- 1,2,3-trimethoxy-5-methylbenzene- 2,6-dimethoxy-4-(2-propenyl)-phenol C14-C22 acids, its methyl or ethyl esters Py-GC-MS chromatogram, pyrolysis at 600oC, pyrolysis time 15 sec. BioEnergy Research Group 17th September 2007 4/9
PY-GC-MS analysis of Etek lignin [commercially available lignin,by-product from EtOH production] Main degradation productsof Etek lignin:- 2-methoxy-4-methyl phenol- 2-methoxy phenol- 2-methoxy-4-vinylphenol- 4-hydroxy-2-methoxy-benzaldehyde- furfural, cyclopentane/hexane derivatives - levoglucosan- anhydrosugars (traces) BioEnergy Research Group seminar 17th September 2007 5/9
PY-GC-MS analysis of Asian lignin [by-product from paper industry] Main pyrolysis productsof Asian lignin:- 2-methoxy-4-vinyl phenol- 2-methoxy-4-methyl phenol- 2-methoxy phenol- 2,6-dimethoxy phenol- 1,2,3-trmethoxybenzene- 1,2,3-trimethoxy-5-methylbenzene- 2,6-dimethoxy-4-(2-propenyl)-phenol- 2,5-dimethyl furan BioEnergy Research Group 17th September 2007 6/9
PY-GC-MS analysis of bio-oil from fast pyrolysis of: Etek lignin • Main compounds identified in • liquids: • acetic acid • 2-cyclopentane-1,4-dione- 2-hydroxy-2-cyclopenten-1-one- phenol- 2-methoxy phenol- levoglucosan + traces of anhydro- and dianhydro- sugars • phenol- 2-methoxy phenol- 4-ethyl phenol- 4-ethyl-2-methoxy phenol Asian lignin BioEnergy Research Group seminar 17th September 2007 7/9
Future work > Characterisation of lignin samples using pyrolysis-gas chromatography-mas spectrometry (PY-GC-MS) at different temperatures (400oC & 500oC; Lignovalue project) > Pyrolysis studies of lignin samples using thermogravimetric analysis (TGA) up to 900oC, heating rates: 5 and 25oC/min. > Problems: Bio-oil (liquid products) analysis: RTX 1701 column(14% cyanopropylphenyl, 86% dimethylpolysiloxane; 60 m, 0.25 mm id.) TGA is not working(will be repaired within two weeks) > In situ studies of monomeric phenols production(HCl pre-treatment, (CH3COO)2Ca, ZnCl2) DTG profile for lignin (Organosolv) pyrolysis;TGA pyrolysis, 25oC/min. in nitrogen BioEnergy Research Group 17th September 2007 8/9