Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

PP-56HYDROGENATION OF CIS-METHYL OLEATE OVER PLATINUMGROUP METALS: CIS-TRANS ISOMERIZATION IMPACTIrina Deliy 1 , Nicoletta Ravasio 2 , Rinaldo Psaro 2 , Irina Simakova 11 Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia,E-mail: simakova@catalysis.ru2 ISTM-CNR, Milano, ItalyHydrogenation of vegetable feedstocks over the platinum group metals could becarried out at the milder conditions (lower temperature and hydrogen pressure) incomparison with Ni catalysts to produce oils both for food and for industrialapplication [1]. In the previous work on methyl linoleate hydrogenation over Pd/MgO[2, 3] it was shown that at methyl linoleate conversion up to 95 % the reactionproduct is the mixture of cis- and trans-isomers of methyl oleate while methylstearate is practically missing in the reaction mixture. The cis-trans isomerization rateincreases sharply after complete methyl linoleate conversion to methyl oleate.In the present work the monounsaturated oleic acid methyl ester was chosen asmodel compound for studying of competitive hydrogenation and cis-transisomerization of unsaturated fatty acids methyl esters over carbon supported VIIIgroup metals.The liquid phase hydrogenation and isomerization of cis methyl oleate over Pd/C,Ru/C, Rh/C, Pt/C and Ir/C catalysts were investigated in the temperature range of298-373 K and hydrogen pressure within 1-10 bar using n-octane as a solvent. Theplatinum group metals supported on carbon catalysts were prepared by thedeposition-precipitation method on the carbon support Sibunit as already reported [4]and characterized by N 2 physisorption, XRD, HREM. GLC, 13 C-NMR and FTIRtechniques were employed to characterize the reaction products.The initial hydrogenation rates of methyl oleate over Pd/C, Ru/C, Rh/C, Pt/C andIr/C catalysts were estimated. It was shown that the most active catalysts for the cismethyl oleate hydrogenation are the Pt/C and Rh/C catalysts. The Ir/C catalyst hasthe low catalytic activity in hydrogenation. Over the explored catalysts the processesof cis methyl oleate double bond isomerization and hydrogenation took placeconcurrently. Among the studied catalysts based on Group 8 metals the highestcatalytic activity in the cis methyl oleate hydrogenation with minor methyl elaidateformation is revealed over Pt catalyst.146