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A new catalyst system, ruthenium-tin boride, was developed for the selective hydrogenation of fatty acid esters to fatty alcohols at 270 °C and a pressure of 640 psi of H2. The yields of fatty alcohols from various long-chain fatty acid esters varied from 70% to 89%. The catalyst had an atomic ratio of ruthenium to tin of 1:1 and could be unsupported or supported on 7-Al203. The importance of the method of preparation using sodium borohydride as the reductant was also demonstrated. A tentative mechanism for the selective activation of the ester carbonyl by the new catalyst system was proposed, based on the surface characterization of the catalysts reported elsewhere.Hydrogenolysis of fatty acid esters to fatty alcohols is a high-pressure reaction. Fatty alcohols are important products that find extensive use for making surfactants of all kinds. Industrially, fatty alcohols are produced using copper chromite based catalysts. These catalysts operate at a high pressure of 4000 psi at temperatures of 250-300 °C. In the literature, only two other catalyst systems, palladium-rhenium and rhodium-tin, have been reported (Traverse et al., 1984;Snappe and Bourneville, 1982) as catalysts for the hydrogenolysis of esters in the pressure range 150-750 psi.

12 53 35 21 50 29 Olein Oil Stearin 37.5 38 45 41.5 39.5 50.5The free fatty acids do have the approximately random distribution that would be expected by random hydrolysis of the triglycerides. In contrast, the mono-and diglycerides have a distribution which is different from random. As previously noted, detergent fractionation concentrates FFA and diglyceride in the olein and monoglyceride in the stearin. The results given in Figure 3 also show that the proportion of P and 0 and of PP, PO and 00 change, with the more unsaturated partial glycerides, like the triglycerides, concentrating in the olein.On bleaching, FFA increases slightly, monoglycerides are reduced and diglycerides are unchanged.After steam refining and deodorization FFA is reduced almost to zero. For palm stearin, the proportions of P and o seem to have altered, but since P (mainly palmitic acid) would be expected to be more volatile, this may be due to experimental error at these very low levels. Monoglycerides also are substantially reduced, with 0 (mainly monoolein) being the only detectable monoglyceride. Total diglycerides show no significant change, but the proportions of PP, PO and 00 do change in the direction of increased random distribution. ABSTRACTKinetics of isomerization of methyl linoleate are studied on ruthenium (5%) on carbon in the temperature range 200-270 C with different solvents. Some equilibrium experiments also are carried out with rhodium and ruthenium catalysts. The reactions taking place are isomerization, hydrogenation and polymerization. The activities and the selectivities are dependent on the nature of the solvent used. Highly protic solvents like methanol or isopropyl alcohol exhibited very high activity and selectivity for hydrogenation, whereas aprotic solvents like hexane or cyclohexane showed very high selectivities for isomerization reaction. The reaction kinetics were found to be further complicated by polymer formation at low solvent concentrations. The effects of temperature, solvent concentration, catalyst quantity and time of reaction also were investigated.