No abstract

No abstract

h i g h l i g h t sOptimum biodiesel yield of 95% was achieved by 50Ca-Ce mixed oxide catalyst. Biodiesel yield increased with increasing basicity and BET surface area. The catalyst can be reused 6 times without significant loss of catalytic activity. Stability of 50Ca-Ce was enhanced by synergic effect between CaO and CeO 2 . Deactivation of catalyst was mainly due to leaching of CaO and pores filling. a b s t r a c tSolid base CaO-CeO 2 mixed oxide catalysts have been synthesized via wet impregnation method and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, temperature-programmed desorption of CO 2 (TPD-CO 2 ) and scanning electron microscopy (SEM). The catalytic activity was determined by transesterification of palm oil. Optimum biodiesel yield, 95%, was achieved by 50Ca-Ce catalyst under the reaction conditions of 5 wt.% of catalyst, methanol to oil molar ratio of 12:1, reaction temperature of 65°C and reaction time of 4 h. The high catalytic activity (95%) of 50Ca-Ce catalyst may be due to strong basicity and high BET surface area, which indicate more number of active sites on the catalyst surface for transesterification process. Besides, 50Ca-Ce catalyst showed better reusability than the bulk CaO where it can be reused up to 6 times without a significant loss of catalytic activity (>80%). The lixiviation of CaO active phase was greatly reduced with the presence of strong synergic interaction between CaO and CeO 2 . Deactivation of the catalyst was mainly due to the leaching of CaO active phase into the methanolic solution and pore-filling by fatty acid or glycerol.

Biodiesel was produced via transesterification of palm oil with methanol in the presence of CaO-Nb

No abstract