Highly effective MnCeOx catalysts for biodiesel production by transesterification of vegetable oils with methanol

This paper reports the results obtained using a novel MnCeOx system in the transesterification reaction of refined sunflower oil with methanol. The performance of such catalysts has been compared with that of common acid supported catalysts. Results obtained revealed that MnCeOx system possesses a superior activity especially by operating at low temperatures (≤120 ◦C). Independently of Mn loading, the redox precipitation method for the preparation of Mn-based systems allowed to obtain always high dispersed catalysts and, as a consequence, a linear relationship between reaction rate and Mn loading was obtained. NH3-TPD and CO2-TPD measurements indicate that MnCeOx systems are characterized by a prevalent nature of basic sites. However, the catalyst performance is the result of a synergic role played by both the surface acid/base character and textural porosit