III International Conference

PP-III-27BIODIESEL SYNTHESIS BY CATALYTIC AND SUPERCRITICAL METODSUshakova L., Lermontov S.Institute of Physiologically Active Substances, RAS, Chernogolovka, Moscow Region, RussiaE-mail: ushakova@ipac.ac.ruEcologically benign methods of biodiesel preparation are described. The methods includethe use of solid superacids as catalysts for vegetable oil transesterification by methanol andthe use of sub- and supercritical methanol without any catalyst for this reaction.Biodiesel is an alternative fuel, which is produced from vegetable and animal oils [1, 2].Its main advantages are: ecological purity, relatively low price and production from renewablesources. Unlike petrochemical products biodiesel is completely degraded in soil and waterand the level of CO emission when biodiesel is burnt is much lower then that of conventionaldiesel fuel. The biodisel production is permanently increasing and it is estimated that in 2020up to 8 % of engines in Europe will use biodiesel.Usually biodiesel is a mixture of methyl and ethyl esters of long- chain fatty acids. It isproduced from vegetable and animal oils by catalytic transesterification by methanol orethanol.Nowadays mainly alkaline catalysts are used for biodisel production because they aremuch more active than acidic ones. Nevertheless, the technological process of alkalinecatalyzedtransesterification is rather complicated due to high demands to starting materials(low water and free acids content must be provided because both deactivate the catalyst).Besides, soap is always produced during the alkaline-catalyzed reaction and soap is difficultlyseparated from the product.We have elaborated two novel non-alkaline procedures for biodiesel preparation.The first procedure employs transesterification of vegetable oil by methanol using solidsuperacids as catalysts. There superacids are based on sulfate modified metal oxides – Al 2 O 3 ,TiO 2 .Heterogeneous catalyst is easily removed from the reaction mixture and can be furtherregenerated. No soap is formed.The second procedure is a sub- and supercritical transesterification without a catalyst.The procedure needs elevated temperature (220 – 260 °C), but no catalyst is used and thereare no separation problems while using this procedure.517