Design of Novel Sulfated Nanozirconia Catalyst for Biofuel Synthesis

Abstract

We report on the elaboration of nanoparticulate SO42––ZrO2 solid acid catalyst for conversion of free fatty acids into biofuel. Three different morphological modifications of zirconia were prepared with the sol–gel method and compared as acid supports: polydispersed nanopowder (PNP), monodispersed nanopowder (MNP), and monodispersed nanoparticles coating (MNC). The size-selected zirconia–oxo–alkoxy (ZOA) nanoparticles of 3.6 nm diameter were prepared in a rapid micromixing reactor and either precipitated (MNP) or deposited on glass beads (MNC). The polydispersed 4/100/500 nm ZOA particles were prepared in nonparent alcohol for realization of PNP powders. The grafting of SO42– groups was realized on the three ZOA supports by wet impregnation method, and three catalysts were prepared after the subsequent drying and thermal treatment stages. The temperature of thermal treatment strongly affects the stability of the solid acid complex and serves to be an important factor of the preparation process. A strong r...