Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

PP-8VALORIZATION OF GLYCEROL BY CONDENSATION WITHACETONE OVER HETEROPOLYACIDS IMMOBILIZED IN SILICAFerreira P. 1 , Fonseca I.M. 2 , Ramos A.M. 2 , Vital J. 2 , Castanheiro J.E. 11 Centro de Química de Évora, Departamento de Química,Universidade de Évora, 7000-671 Évora, Portugal, E-mail: jefc@uevora.pt2 REQUIMTE, CQFB, Faculdade de Ciências e Tecnologia,Universidade Nova de Lisboa, 2829-516 Caparica, PortugalGlycerol is the by-product of biodiesel production by transesterification oftriglyceride with methanol or ethanol. For every 9 kg of biodiesel produced, about 1kg of a crude glycerol is formed. An increase of glycerol production and a pricedecrease becomes the glycerol a promising low-cost feedstock for producing valueaddedchemicals or materials [1,2]. A possible solution to the problem, it is thecondensation of glycerol with acetone, which provides a branched oxygen-containingcompound. These compounds could be used as an additive in the biodieselformulation. The products of glycerol acetalisation are (2,2-Dimethyl-[1,3]dioxan-4-yl)-methanol (solketal) and 2,2-Dimethyl-[1,3]dioxan-5-ol [3,4]. Heteropolyacids(HPAs) with the Keggin structure are known to be highly active heterogeneouscatalysts in acid type reactions. A greatvariety of supports have been used assupport to immobilize HPAs [5]. In this work,we report the acetalisation of glycerol oversilica-included heteropolyacids. Thetungstophosphoric acid (PW),molybdophosphoric acid (PMo), tungstosilisicacid (SiW) and molybdosilisic acid (SiMo)were immobilized in silica by sol-gel method,Fig. 1. Acetalisation of glycerol over according to Y. Izumi et al. [6]. It washeteropolyacids.observed that the catalytic activity decreasesin the series: PW_S > SiW_S > PMo_S > SiMo_S (Fig. 1). All catalyst exhibited goodvalues of selectivity to solketal (about 98% near complete conversion).[1]. Y. Zheng, X. Chen, Y. Shen, Chem. Rev., 2008 (108) 5253–5277.[2]. P. Ferreira, I.M. Fonseca, A.M. Ramos, J. Vital, J.E. Castanheiro, Appl. Catal. B:Env., 2009 (91)416-422.[3]. C.X. A. da Silva, V.L.C. Gonçalves, C.J.A. Mota, Green Chem., 2009 (11) 38-41.[4]. J. Deutsch, A. Martin, H. Lieske, J. Catal., 2007 (245) 428-435.[5]. I.V. Kozhevnikov, Chem. Rev., 1998 (98) 171-198.[6]. Y. Izumi, K. Hisano, T. Hida, Appl. Catal. A:Gen., 1999 (181) 277-282.96