Gustavo Pereira Reis
UFMG, Brazil
Title: Performance of CaO from different sources as a catalyst precursos in soybean oil transesterification: kinetics and leaching evaluation
Biography
Biography: Gustavo Pereira Reis
Abstract
Calcium oxide (CaO) has been studied as one of the most efficient heterogeneous catalysts for biodiesel production, but there are few studies about the effects of CaO morphology on calcium leaching and catalyst activity. In the present work, soybean transesterification was performed using CaO from different sources (commercial, synthesized from chicken eggshell and produced by a carbothermal route) to develop a comparative study. The 1H NMR results showed that the soybean oil transesterification catalyzed with CaO, derived from all sources, yielded greater than 93% (m/m) methyl esters, 4 h reflux, a molar methanol: oil ratio of 12:1 and 3% catalyst. The amount of leached calcium was 219 ppm for the biodiesel synthesized with CaO derived from commercial sources, 194 ppm for CaO from eggshell and 93 ppm for CaO s from a carbothermal route. As consequence of higher Ca leaching content, CaO-com precursor presented higher rate constant. This can be explained by the prompt reaction of Ca leaching and glycerol, yielding calcium diglyceroxide, which is the main catalytic specimen. The study showed that the homogeneous contribution from the leached species can be considered negligible. The heterogeneous catalysis was confirmed for all different CaO sources studied.