title: Catalyst-free fatty acid methyl ester production from wet activated sludge under subcritical water and methanol condition.
abstract: Wet activated sludge was converted directly into biodiesel using water as hydrolysis reagent to enhance the extraction of lipid in activated sludge, and as catalyst for the conversion of neutral lipids into biodiesel under subcritical conditions. At 175°C, 3.5MPa, a methanol to sludge ratio of 30 (mL/g) and a sludge water content of 84wt.%, about 90% conversion to fatty acid methyl esters was achieved within 24h without the need for conventional catalysts such as KOH and H(2)SO(4). Since water is employed as a catalyst, its removal is not required; therefore, the processing costs for producing biodiesel from activated sludge are reduced. The method has the potential for applications to other feedstock with high water contents such as micro-algae.
authors.affiliation: Department of Chemical Engineering, National Taiwan University of Science and Technology, 43, Keelung Road, Section 4, Taipei 10607, Taiwan.
authors.forename: Lien Huong
authors.initials: LH
authors.lastname: Huynh
authors.forename: Phuong Lan
authors.initials: PL
authors.lastname: Tran Nguyen
authors.forename: Quoc Phong
authors.initials: QP
authors.lastname: Ho
authors.forename: Yi-Hsu
authors.initials: YH
authors.lastname: Ju
mesh_terms: D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D004951:Esterification; D004952:Esters / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis*; D006586:Hexanes / Q000737:chemistry; D000432:Methanol / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D004952:Esters; D005227:Fatty Acids; D006586:Hexanes; D012722:Sewage; D014867:Water; D000432:Methanol