title: Pyrolysis of lignin in the presence of tetramethylammonium hydroxide: a convenient method for S/G ratio determination.
abstract: Pyrolysis-gas chromatography in the presence of tetramethylammonium hydroxide (TMAH) was applied to the determination of the ratio of the abundances of the syringyl beta-aryl ether subunits to those of the guaiacyl equivalents (S/G) in lignin. Diazomethane-methylated kenafs (Hibiscus cannabinus and Hibiscus sabdariffa) and beech (Fagus crenata) in situ lignins were employed. Relative abundances of pyrolysis products derived from the guaiacyl and syringyl beta-aryl ether subunits were determined. The S/G ratios for in situ lignins were obtained with average 3.1% relative standard deviation for a minimum of six repeated runs. The S/G ratios determined by pyrolysis in the presence of TMAH agreed well with those determined by thioacidolysis, with a significant linear regression (R(2) = 0.9867). The results showed that pyrolysis with TMAH is an effective tool for obtaining information on the S/G ratio for in situ lignins.
authors.affiliation: Institute of Agricultural and Forest Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan. ken@sakura.cc.tsukuba.ac.jp
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kuroda
authors.forename: Natsuno
authors.initials: N
authors.lastname: Nishimura
authors.forename: Akiko
authors.initials: A
authors.lastname: Izumi
authors.forename: Donald R
authors.initials: DR
authors.lastname: Dimmel
mesh_terms: D018533:Biomass; D032462:Cycadopsida / Q000737:chemistry*; D004987:Ethers / Q000737:chemistry; D006358:Hot Temperature; D008031:Lignin / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds; D012044:Regression Analysis; D019685:Rosales / Q000737:chemistry
chemical_list: D004987:Ethers; D000644:Quaternary Ammonium Compounds; D008031:Lignin; C027917:tetramethylammonium