Catalytic Activity of Sulfated Iron-Tin Mixed Oxide for Esterification of Free Fatty Acids in Crude Palm Oil: Effects of Iron Precursor, Calcination Temperature and Sulfate Concentration

Kamchai Nuithitikul 1 , 1 , Worawoot Prasitturattanachai 2 , 2  and Jumras Limtrakul 3 , 3
  • 1 King Mongkut's University of Technology North Bangkok,
  • 2 King Mongkut's University of Technology North Bangkok,
  • 3 Kasetsart University,

The activities of sulfated iron-tin mixed oxide catalysts for esterification of free fatty acids in crude palm oil were investigated. The iron-tin mixed oxides were prepared from co-precipitation method when the iron content was fixed at 10 mol%. Types of iron precursor, sulfate concentration and calcination temperature were varied. The optimum study in the esterification reaction variables (stirring speed, reaction time, catalyst loading, methanol/oil molar ratio and reaction temperature) was also conducted with the best sulfated iron-tin mixed oxide catalyst. The findings show that iron sulfate is the best precursor. The activities of sulfated iron-tin mixed oxide catalysts increase with sulfate concentration. The optimum calcination temperature to prepare sulfated iron-tin mixed oxides is 450°C. The addition of iron oxide into sulfated tin oxide improves the stability of the catalyst during the reusability process. Therefore, sulfated iron-tin mixed oxide is a better candidate than sulfated tin oxide for esterification of free fatty acids. For the esterification study, the optimum reaction conditions are: the stirring speed of 250 rpm, the catalyst loading of 4.5 wt% of the oil, the methanol/oil molar ratio of 14.2, the reaction temperature of 80°C and the reaction time of 3 h.

Purchase article
Get instant unlimited access to the article.
Log in
Already have access? Please log in.

Log in with your institution

Journal + Issues

The International Journal of Chemical Reactor Engineering covers the broad fields of theoretical and applied reactor engineering. The IJCRE covers topics drawn from the substantial areas of overlap between catalysis, reaction and reactor engineering. Authors include notable international professors and R&D industry leaders.