Thesis (M.Sc.)--Chulalongkorn University, 2000

The study of the partial and selective hydrogenation of soybean oil was carried out using bimetallic catalysts. The catalysts were 5%Ni-5%W, 5%Ni-10%W, 5%Co-5%W, and 5%Co-10%W deposited on alumina support. The operating conditions, including temperature, hydrogen pressure, and reaction time, were studied. It was found that the best catalyst was 5%Ni-10%W onalumina. The suitable condition to produce oleic acid using this catalyst were at the reaction temperature at 150 ํC, hydrogen pressure at 150 psig, reaction time at 2 hours, agitation speed at 500 rpm, and catalyst concentration at 10% by weight of oil. The product obtained from this condition, had iodine value at 90, consisting of 9.09% palmitic acid, 9.91% stearic acid, 72.58% oleic acid, and 8.42% linoleic acid by weight of oil. Meanwhile, linolenic acid was completely hydrogenated. The hydrogenated oil was separated into two parts; the saturated fatty acid part and the unsaturated fatty acid part, by winterization method. The unsaturated fatty acid part contained 87.58% oleic acid by weight of total unsaturated fatty acid part. The hydrogenation using 5%Ni-10%W on alumina provided the highest amount of oleic acid in the hydrogenated products compared to other catalysts under the same condition