Novel iron sand-derived α-Fe2O3/CaO2 bifunctional catalyst for waste cooking oil-based biodiesel production.

The main aim of this work was to develop a heterogeneous Fe2O3/CaO2 bifunctional catalyst prepared from iron sand and 3 different CaO2 sources (CaCO3, Ca (OH)2, and limestone) using wet impregnation and calcination methods for biodiesel production. The effects of different CaO2 sources and Fe/Ca ratio in the catalyst were investigated to provide insight into the catalyst character and biodiesel yield. X-ray diffraction, X-ray fluorescence, and scanning electron microscopy analyses were used to characterize the catalyst. CaCO3 was concluded as the best CaO2 source, while the best Fe/Ca configuration was found to be 1:4, giving the highest biodiesel yield (97.0401%) with no diglycerides. Greater addition of Fe loading would result in an amorphous structure, and all catalysts were relatively crystalline. Fe was concluded to favor the esterification reaction and biodiesel formation, while CaO2 was seen to favor the transesterification reaction and fatty acid methyl ester (FAME) formation. The catalyst mechanism was also established in this study, where esterification of free fatty acid (FFA) and glycerol took place on the acid site to produce diglyceride and transesterification of triglyceride by methanol occurred on the basic site.

Reaction rate law model and reaction mechanism covering effect of plasma role on the transesterification of triglyceride and methanol to biodiesel over a continuous flow hybrid catalytic-plasma reactor.

This study investigated predictions of reaction mechanisms and reaction rate law model covering effect of plasma role on the heterogeneous catalytic reaction of triglyceride and methanol to produce biodiesel (fatty acid methyl ester - FAME or fatty acid alkyl ester - FAAE) over a continuous flow hybrid catalytic-plasma reactor. This catalytic reaction was carried out in a dielectric-barrier discharge plasma reactor over 5 wt% K2O/CaO-ZnO catalyst under conditions of atmospheric pressure and the reactor temperature of 65 °C. During the hybrid catalytic-plasma reaction system, the voltage, the catalyst diameter, and the Weight Hourly Space Velocity (WHSV) were kept constant at 5 kV, 5 mm, and 1.186/min, respectively. It was found that transesterification reaction with the hybrid roles of catalytic and plasma achieved 77.2% biodiesel yield. Kinetic studies of this transesterification reaction over a continuous flow hybrid catalytic-plasma reactor suggested following Eley-Rideal mechanism model, where the methanol adsorbed on the catalyst surface reacted with triglycerides in bulk phase to produce an adsorbed methyl ester and glycerol in bulk phase. The possible reaction rate law model found is: -rTG = rME = rs = (0.0078∗(0.0061∗CTG∗CM 3-3.0302 × 10-6∗CME 3∗CG))/(0.1827∗CM+ 0.0145∗CME+1)3 gmol/gcat.min. This reaction rate law model was useful to design reactor of the hybrid catalytic-plasma chemical reaction system for biodiesel production.

Effect of dealumination on the acidity of zeolite Y and the yield of glycerol mono stearate (GMS).

Research on the production of Glycerol Monostearate from glycerol using dealuminated Zeolite Y catalysts has been carried out. Optimization of the dealumination process is conducted using the help of statistical software 10, where the variables used are acid concentration (5-7 M), temperature of dealumination (55-70 °C) and time of dealumination (2-6 h). The acidity characterization test of dealuminated Zeolite Y using ammonia and pyridine solution. Glycerol Monostearate yield was obtained by GC-MS test that was carried out on 2 samples zeolite Y catalyst with the highest value of total and surface acidity of zeolite Y which produced 2.18% and 4% yield of Glycerol Monostearate. The two samples showed that the greater the acidity, the GMS yield was also greater. Compared to previous studies it was found that ZSM-5 catalyst has a higher acidity value than zeolite Y so that the yield of Glycerol Monostearate is higher with the use of ZSM-5 than Zeolite Y.