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The solid solutions between the spinels MgAl2O4 and MgFe2O4 with the general formula MgAl2 − xFexO4 are synthesised and characterised by X‐ray diffraction and application of Vegard's law. The cation distribution in this spinel system is determined from X‐ray and magnetic susceptibility measurements. The electrical and magnetic properties of the system are also studied and the interesting variation of these properties are explained in terms of the changes in spinel structure.

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.