Jeffrey C S Wu
National Taiwan University, Taiwan
Title: Biodiesel and glycerol transesterification by layered double hydroxides in stirring packedbedreactor
Biography
Biography: Jeffrey C S Wu
Abstract
In this research, we transesterifi cated (1) triglycerides to synthesize biodiesel and; (2) its byproduct glycerol to form a more valuable chemical, glycerol 1,2-carbonate, using layered double hydroxides (LDHs), specifi cally Mg-Al LDH. We studied the diff erent Mg/ Al ratios in catalyst preparation, calcination temperatures of LDH, reaction temperatures, catalyst loadings and the molar ratios of dimethyl carbonate/glycerol, etc., which are critical factors in both transesterifi cation reactions. We had Mg-Al LDH coated on the 3mm spherical α-Al2O3 catalyst in the stirring packed-bed reactor. Mg-Al LDH was fi rst calcined and then rehydrated with
decarbonated water-glycerol solution to reconstruct the layer structure and also to protect the catalyst deactivation by air at the same time. In biodiesel synthesis, the yield reached 65.72% in 4 hours under 60oC, 87.45% in 3 hours under 100oC, when the methanol / soybean oil molar ratio was set to be 30, and 10wt% Mg/Al=5 LDH was used in the reaction. Th e glycerol transesterifi cation was carried out by dimethyl carbonate/glycerol molar ratio 16 with the existence of solvent, dimethyl sulfoxide, using 10wt% Mg/Al=5 LDH on spherical α-Al2O3 at 95oC. Th e yield of glycerol 1,2-carbonate could reach up to 93.4% within 7.5 hours. When applying 10wt% catalyst of Mg/Al=5 LDH on spherical α-Al2O3 into the stirring packed-bed reactor, the yield of glycerol 1,2-carbonate reached to 80.17% within 11 hours under the residence time 22.5 hours, and dimethyl carbonate/glycerol molar ratio = 16 at 90oC.