title: Synthesis of biodiesel from a model waste oil feedstock using a carbon-based solid acid catalyst: reaction and separation.
abstract: A solid acid catalyst that can keep high activity and stability is necessary when low cost feedstocks are utilized for biodiesel synthesis because the reaction medium contains a large amount of water. Three solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt. The structure of these catalysts was characterized by a variety of techniques. A new process that used the coupling of the reaction and separation was employed, which greatly improved the conversion of cottonseed oil (triglyceride) and free fatty acids (FFA) when a model waste oil feedstock was used. The vegetable oil asphalt-based catalyst showed the highest catalytic activity. This was due to the high density and stability of its acid sites, its loose irregular network, its hydrophobicity that prevented the hydration of -OH species, and large pores that provided more acid sites for the reactants.
authors.affiliation: Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Shu
authors.forename: Zeeshan
authors.initials: Z
authors.lastname: Nawaz
authors.forename: Jixian
authors.initials: J
authors.lastname: Gao
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Liao
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Dezheng
authors.initials: D
authors.lastname: Wang
authors.forename: Jinfu
authors.initials: J
authors.lastname: Wang
mesh_terms: D000821:Animal Feed; D056804:Biofuels; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D004736:Energy-Generating Resources; D004951:Esterification; D005230:Fatty Acids, Nonesterified / Q000737:chemistry; D006838:Hydrocarbons / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D013696:Temperature; D014280:Triglycerides / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D056804:Biofuels; D005230:Fatty Acids, Nonesterified; D006838:Hydrocarbons; D014280:Triglycerides; D014867:Water; D002244:Carbon; D006859:Hydrogen; C006647:asphalt