title: Lignin depolymerisation in supercritical carbon dioxide/acetone/water fluid for the production of aromatic chemicals.
abstract: Valorisation of lignin plays a key role in further development of lignocellulosic biorefinery processes the production of biofuels and bio-based materials. In the present study, organosolv hardwood and wheat straw lignins were converted in a supercritical fluid consisting of carbon dioxide/acetone/water (300-370°C, 100bar) to a phenolic oil consisting of oligomeric fragments and monomeric aromatic compounds with a total yield of 10-12% based on lignin. These yields are similar to the state-of-the-art technologies such as base-catalysed thermal processes applied for lignin depolymerisation. Addition of formic acid increases the yield of monomeric aromatic species by stabilizing aromatic radicals. Supercritical depolymerisation of wheat straw and hardwood lignin yielded monomeric compounds in different compositions with a maximum yield of 2.0% for syringic acid and 3.6% for syringol, respectively. The results of the present study showed that under the applied conditions competition occurred between lignin depolymerisation and recondensation of fragments.
authors.affiliation: Wageningen University, Food and Biobased Research, Wageningen, The Netherlands. richard.gosselink@wur.nl
authors.forename: Richard J A
authors.initials: RJ
authors.lastname: Gosselink
authors.forename: Wouter
authors.initials: W
authors.lastname: Teunissen
authors.forename: Jan E G
authors.initials: JE
authors.lastname: van Dam
authors.forename: Ed
authors.initials: E
authors.lastname: de Jong
authors.forename: Göran
authors.initials: G
authors.lastname: Gellerstedt
authors.forename: Elinor L
authors.initials: EL
authors.lastname: Scott
authors.forename: Johan P M
authors.initials: JP
authors.lastname: Sanders
mesh_terms: D000096:Acetone / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism*; D010636:Phenols / Q000032:analysis; D058105:Polymerization; D013696:Temperature; D014908:Triticum / Q000737:chemistry; D014866:Waste Products / Q000032:analysis; D014867:Water / Q000737:chemistry*; D014934:Wood
chemical_list: D006841:Hydrocarbons, Aromatic; D010636:Phenols; D014866:Waste Products; D014867:Water; D000096:Acetone; D002245:Carbon Dioxide; D008031:Lignin