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PP-I-49EXPERIMENTAL STUDY OF THE HALIDE-FREE CARBONYLATIONOF DIMETHYL ETHER TO METHYL ACETATE ON BIFUNCTIONALRh/Cs 1.5 H 1.5 PW 12 O 40 CATALYSTReshetnikov S.I., Izvekova A.A., Volkova G.G.Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5,Novosibirsk, 630090, Russia, E-mail: ggvolkova@catalysis.ruAcetic acid is an important industrial chemical which is manufactured on a largescale. The main route to acetic acid is through the carbonylation of methanol in theMonsanto process which uses a homogeneous rhodium catalyst and halidepromoter. Main disadvantages of this process are: a) halides are highly corrosive andare poisons for many types of catalysts b) it is difficult to separate the products andcatalyst. These problems may be overcome by developing heterogeneous catalystthat can operate effectively without halide promoter. Studies at Boreskov Institute ofCatalysis have shown that acidic cesium salts of 12-tangstophosphoric acidpromoted with rhodium revealed high activity in the iodide-free carbonylation of thedimethyl ether (DME) to methyl acetate (MA) [1] that is one order of magnitudehigher than the activity of the rhodium salts of the same acid supported on silica [2].CH 3 -O-CH 3 + CO → CH 3 -CO-O-CH 3Investigations of the reaction over 1%Rh/Cs 1.5 H 1.5 PW 12 O 40 catalyst were carriedout at the excess CO, ratio DME : CO =1:19 and 1:10, temperature = 200, 220 and250°C; space velocity = 2, 5, 10 liters hour –1 , pressure 10 atm. It was observed thatDME conversion increased with temperature and contact time raise. It was alsoshown that DME conversion was inversely proportional to initial DME concentrationand it did not depend on CO concentration. The rate constants and activation energyfor DME carbonylation at the excess CO were evaluate assuming that the reaction isfirst order in DME. E=12,3 Kcal mol –1 . It may be suggested that DME carbonylationreaction occurs through Eley-Rideal route where CO molecule from gas phaseinteracts with adsorbed molecule of DME:References1. DME+ [ ] = [DME]; 2. [DME] + CO → MA + [ ].[1]. G.G. Volkova, L.M. Plyasova, A.N. Salanov, G.N. Kustova, T.M. Yurieva, V.A. Likholobov, Catal. Lett.2002, 80, 175; G.G. Volkova, L.M. Plyasova, L.N. Shkuratova, A.A. Budneva, E.A. Paukshtis,M.N. Timofeeva, V.A. Likholobov, Stud. Sur. Sci. Catal. 2004, 147, 403.[2]. W.R. Wegman, European Patent 0353 722 1989.AcknowledgementsThis work is supported by Federal Target Program (FTP) ”Science, Academic andTeaching Staff of Innovative Russia for 2009-2013”. Contract P253.307