title: Extraction of phenols from lignin microwave-pyrolysis oil using a switchable hydrophilicity solvent.
abstract: Microwave pyrolysis of lignin, an aromatic polymer byproduct from paper-pulping industry, produces char, gases, and lignin pyrolysis oil. Within the oil are valuable phenolic compounds such as phenol, guaiacol and catechol. In this work, we describe a method using switchable hydrophilicity solvents (SHS) to extract phenols as a mixture from lignin microwave-pyrolysis oil at the scale of 10 g of bio-oil. Even at this small scale, losses are small; 96% of the bio-oil was recovered in its three fractions, 72% of guaiacol and 70% of 4-methylguaiacol, the most abundant phenols in the bio-oil, were extracted and 91% of the solvent SHS was recovered after extraction. The starting material (lignin microwave-pyrolysis oil) and the three fractions resulted from SHS extraction were characterized by GC-MS and quantitative (13)C{(1)H} and (31)P{(1)H} NMR spectroscopy.
authors.affiliation: Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Dongbao
authors.initials: D
authors.lastname: Fu
authors.affiliation: Department of Chemical Engineering, Ecole Polytechnique de Montreal, Quebec H3C 3A7, Canada.
authors.forename: Sherif
authors.initials: S
authors.lastname: Farag
authors.affiliation: Department of Chemical Engineering, Ecole Polytechnique de Montreal, Quebec H3C 3A7, Canada.
authors.forename: Jamal
authors.initials: J
authors.lastname: Chaouki
authors.affiliation: Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario K7L 3N6, Canada. Electronic address: jessop@chem.queensu.ca.
authors.forename: Philip G
authors.initials: PG
authors.lastname: Jessop
mesh_terms: D001709:Biotechnology / Q000379:methods*; D005591:Chemical Fractionation; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008872:Microwaves; D009821:Oils / Q000737:chemistry*; D010636:Phenols / Q000302:isolation & purification*; D012997:Solvents / Q000737:chemistry*
chemical_list: D009821:Oils; D010636:Phenols; D012997:Solvents; D008031:Lignin
keywords: Extraction; Lignin; Phenols; Pyrolysis oil; Switchable solvents