DEVELOPMENT OF HETEROGENEOUS CATALYSTS FOR BIODIESEL PRODUCTION


Thesis Type: Postgraduate

Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey

Approval Date: 2009

Student: AYFER BARTAN

Co-Consultant: İRFAN AR, MUZAFFER BALBAŞI

Abstract:

Biodiesel is produced by transesterification of vegetable oils, fats and waste oils with short-chain alcohols (i.e.,methanol, ethanol, etc.) in the presence of a catalyst and it is used as a fuel. Glycerine is the byproduct of this reaction. One of the most important parameter that effects the biodiesel production efficiency is the type of the catalyst. In biodiesel production reaction both homogeneous or heterogeneous catalyst can be used. Although homogeneous catalysts provide high yield, the factors such as soap formation, high reactants consumption and extra separation cost have the negative effect on production cost. Therefore the studies for development of regenerable heterogeneous catalyst that prevents the soap formation, and having high yield, gain big importance in recent years. In this study naturel zeolite, volcanic tufa and CaO were used as naturel support material where as MCM-41 and commercial zeolite (Z-700 and Z-400) were used as synthetic ones. Active materials such as KOH, KI, NaOH and Mg(NO3)2 were loaded on the support materials by wet impregnation method and they used as catalyst. Activity of naturel supports were also investigated by performing a set of experiments in which these materials were used as catalyst without active material loading. Effects of the temperature, catalyst concentration, methanol/oil ratio, reaction time, type of the catalyst, kind of oil, supporting material and size distribution on ester conversion efficiency were investigated. It was found that yield is increase with the increasing temperature, amount of catalyst, increasing active material concentration, methanol to oil ratio and with increasing reaction time up to optimum condition. On the other hand, it was observed that yield was change with type of the catalyst and the best conversion efficiency was obtained when KI loaded naturel zeolite A was used as the catalyst. It was also observed that the efficiency decreases with increasing particle size.