Effect of calcination temperature on the physicochemical and catalytic properties of SZSBA-15 catalyst in the production of monopalmitin

Abstract

ABSTRACTSulfated zirconia on SBA-15 catalysts with different calcination temperatures (450, 550, 600 and 650°C) were synthesized through urea hydrolysis method. The catalysts were characterized using N2 adsorption–desorption analysis, scanning electron microscopy, energy dispersive X-ray, transmission electron microscopy, thermogravimetric analysis, temperature-programmed desorption of ammonia (NH3–TPD), X-ray diffraction, and determination of surface acidity by HCl titration method. The catalyst’s characteristics and their correlation with the catalytic activity in the esterification of palmitic acid with glycerol were particularly investigated. The characterization results revealed that the morphology of all catalysts remained virtually unaffected with increasing calcination temperature but the surface area and pore volume of the catalysts showed some reduction. Pore diameter was not significantly affected by the calcination temperature which indicated the stability of the porous catalysts. Furthermore, the increase in the calcination temperature exceeding 600°C would reduce the catalytic activity toward monopalmitin due to a decrease in the active acid sites concentration and acidic strength of the catalyst as a result of sulfur decomposition.