title: Understanding low-lipid algae hydrothermal liquefaction characteristics and pathways through hydrothermal liquefaction of algal major components: crude polysaccharides, crude proteins and their binary mixtures.
abstract: Crude polysaccharides and proteins extracted from algae were chosen as model materials to investigate the hydrothermal liquefaction (HTL) characteristics and pathways of low-lipid algae. Liquefaction behavior of the two individuals and their binary mixtures with different mass ratios were evaluated under different temperatures. Formation pathways of bio-oil from crude polysaccharides/proteins were proposed. Results showed that polysaccharides had a small contribution to bio-oil (<5%) and approximately 60% distributed in aqueous phase, while proteins played a crucial role on bio-oil formation (maximum 16.29%). Bio-oil from polysaccharides mainly contained cyclic ketones and phenols and from proteins composed of pyrazines, pyrroles and amines. Interaction between polysaccharides and proteins forming polycyclic nitrogenous compounds had a negative effect on bio-oil yield at 220 and 260°C. However, their further decomposition caused increase of bio-oil yield at 300°C. Mixture liquefaction obtained the highest higher heating value (HHV) of bio-oil and energy recovery than polysaccharides/proteins liquefaction at 300°C.
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Yang
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
authors.forename: Xianguo
authors.initials: X
authors.lastname: Li
authors.affiliation: College of Chemistry, Jilin University, Changchun 130012, China.
authors.forename: Zihui
authors.initials: Z
authors.lastname: Li
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
authors.forename: Chenhong
authors.initials: C
authors.lastname: Tong
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China. Electronic address: fenglj@ouc.edu.cn.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Feng
mesh_terms: D020418:Algal Proteins / Q000032:analysis*; D056804:Biofuels / Q000032:analysis; D001709:Biotechnology / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D005740:Gases / Q000032:analysis; D008055:Lipids / Q000737:chemistry*; D009584:Nitrogen; D010084:Oxidation-Reduction; D011134:Polysaccharides / Q000032:analysis* / Q000737:chemistry; D013696:Temperature; D014867:Water
chemical_list: D020418:Algal Proteins; D056804:Biofuels; D005740:Gases; D008055:Lipids; D011134:Polysaccharides; D014867:Water; D009584:Nitrogen
keywords: Crude polysaccharides; Crude proteins; Hydrothermal liquefaction characteristics; Maillard reaction; Pathways