title: Oxidative degradation of biorefinery lignin obtained after pretreatment of forest residues of Douglas Fir.
abstract: Harvested forest residues are usually considered a fire hazards and used as "hog-fuel" which results in air pollution. In this study, the biorefinery lignin stream obtained after wet explosion pretreatment and enzymatic hydrolysis of forestry residues of Douglas Fir (FS-10) was characterized and further wet oxidized under alkaline conditions. The studies indicated that at 10% solids, 11.7wt% alkali and 15min residence time, maximum yields were obtained for glucose (12.9wt%), vanillin (0.4wt%) at 230°C; formic acid (11.6wt%) at 250°C; acetic acid (10.7wt%), hydroxybenzaldehyde (0.2wt%), syringaldehyde (0.13wt%) at 280°C; and lactic acid (12.4wt%) at 300°C. FTIR analysis of the solid residue after wet oxidation showed that the aromatic skeletal vibrations relating to lignin compounds increased with temperature indicating that higher severity could result in increased lignin oxidation products. The results obtained, as part of the study, is significant for understanding and optimizing processes for producing high-value bioproducts from forestry residues.
authors.affiliation: Bioproducts, Sciences and Engineering Laboratory, Washington State University, Tri-Cities, Richland, WA 99354, United States.
authors.forename: Keerthi
authors.initials: K
authors.lastname: Srinivas
authors.affiliation: Biotechnology Department, Engineering School of Lorena, University of São Paulo, Lorena SP 12.602-810, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: de Carvalho Oliveira
authors.affiliation: Bioproducts, Sciences and Engineering Laboratory, Washington State University, Tri-Cities, Richland, WA 99354, United States.
authors.forename: Philip Johan
authors.initials: PJ
authors.lastname: Teller
authors.affiliation: Biotechnology Department, Engineering School of Lorena, University of São Paulo, Lorena SP 12.602-810, Brazil.
authors.forename: Adilson Roberto
authors.initials: AR
authors.lastname: Gonҫalves
authors.affiliation: Center for NMR Spectroscopy, Washington State University, Pullman, WA 99164, United States.
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Helms
authors.affiliation: Bioproducts, Sciences and Engineering Laboratory, Washington State University, Tri-Cities, Richland, WA 99354, United States. Electronic address: bka@wsu.edu.
authors.forename: Birgitte Kaer
authors.initials: BK
authors.lastname: Ahring
mesh_terms: D065928:Forests; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry*; D010084:Oxidation-Reduction; D028224:Pseudotsuga / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*
chemical_list: D008031:Lignin
keywords: Biochemical; Biorefinery; Douglas Fir; Lignin; Wet oxidation