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Muhammad Ayoub a, M.S. Khayoon a,b, Ahmad Zuhairi Abdullah a.* Synthesis of oxygenated fuel bioadditives via the solventless etherification of glycerol.

School of Chemical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang, Malaysia
Bioresource Technology (Impact Factor: 5.04). 02/2012; DOI: 10.1016/j.biortech.2012.02.103

ABSTRACT The synthesis of oxygenated fuel additives via solvent free base-catalyzed etherification of glycerol is reported. The products of glycerol etherification are diglycerol (DG) and triglycerol (TG) with DG being the favorable one. The catalytic activity of different homogeneous alkali catalysts (LiOH, NaOH, KOH and Na2CO3) was investigated during the glycerol etherification process. LiOH exhibited an excellent catalytic activity during this reaction, indicated by the complete glycerol conversion with a corresponding selectivity of 33 % toward DG. The best reaction conditions were a reaction temperature of 240 oC, a catalyst/glycerol molar ratio of 0.02 and a reaction time of 6 h. The influences of various reaction variables such as nature of the catalyst, catalyst loading, reaction time and reaction temperature on glycerol etherification were elucidated. Industrially, the findings attained in this study might contribute towards promoting the biodiesel industry through utilization of its by-products.

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