title: Conversion of Undaria pinnatifida residue to glycolic acid with recyclable methylamine in low temperature hydrothermal liquefaction.
abstract: The conversion of Undaria pinnatifida residue to glycolic acid was carried out using methylamine as catalyst by hydrothermal method at relatively low temperature. GC-MS and HPLC were used to identify the composition of bio-oil and liquid products which provide the knowledge of the chemical reaction pathways of the hydrothermal liquefaction. The main liquid product was organic acid which contained glycolic acid, lactic acid, formic acid and acetic acid. And the major organic acid was glycolic acid with the highest yield of 46.52% or 33.98% of dry biomass. Methylamine promoted the dissolution of cellulose from Undaria pinnatifida residue, and significantly improved the yield of glycolic acid. The mechanism of HTL was investigated and the results show that the carbocation C3was attacked by methylamine molecule which led to the high yield of glycolic acid. In addition, the recovery of methylamine was studied and the highest recovery rate reached 99.28%.
authors.affiliation: Harbin Institute of Technology, School of Marine Science and Technology, West Culture Road 2, Weihai, Shandong, China.
authors.forename: Yongxing
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Harbin Institute of Technology, School of Marine Science and Technology, West Culture Road 2, Weihai, Shandong, China. Electronic address: renxiulian@126.com.
authors.forename: Xiulian
authors.initials: X
authors.lastname: Ren
authors.affiliation: Harbin Institute of Technology, School of Marine Science and Technology, West Culture Road 2, Weihai, Shandong, China.
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Wei
mesh_terms: D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D002482:Cellulose / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003080:Cold Temperature; D008401:Gas Chromatography-Mass Spectrometry; D006016:Glycolates / Q000138:chemical synthesis* / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry; D008744:Methylamines / Q000737:chemistry*; D044648:Undaria / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D006016:Glycolates; D008744:Methylamines; D014867:Water; C031149:glycolic acid; D019344:Lactic Acid; D002482:Cellulose; C027451:methylamine
keywords: Bio-oil; Glycolic acid; Hydrothermal liquefaction; Methylamine; Organic acid