Heterogeneous and efficient transesterification of Jatropha curcas L. seed oil to produce biodiesel catalysed by nano-sized SO 4 2− /TiO 2

Developing high-efficiency hetero-catalysts for transesterification reaction is of great importance in the production of biodiesel from Jatropha curcas L. seed oil (JO). Here, we synthesized a series of sulfated TiO 2 by treating with varying H 2 SO 4 concentration (SO 4 2− /TiO 2 ) and TiO 2 catalysts and applied to the transesterification of JO. Furthermore, these heterostructures were characterized by many characterization methods including XRD, FT-IR, N 2 -adsorption, SEM, TEM, TG, py-IR and NH 3 -TPD, and their catalytic performance was investigated under various operating conditions. The results reveal that both the Brønsted and Lewis acid sites are presented in the SO 4 2− /TiO 2 catalysts, while only Lewis-type sites are observed in the TiO 2 catalyst. And the acid intensity, surface area and mesoporous volume of catalysts are improved obviously after treating TiO 2 with sulfuric acid. Then the SO 4 2− /TiO 2 catalysts exhibit much higher catalytic activity than TiO 2 catalyst, which is attributed to the larger surface area and mesoporous volume and stronger acidity. Furthermore, the reusability behaviour of 1.5 SO 4 2− /TiO 2 catalyst in the transesterification of JO was also studied.