III International Conference

PP-II-106DME SYNTHESIS FROM METHANOL AND SYNGAS: EXPERIMENT ANDKINETIC MODELINGRozovskii A.Ya., Zavalishin I.N., Lin G.I., Samokhin P.V., Volnina E.A., Kipnis M.A.,Belostostky I.A.Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, RussiaE-mail: rozovsk@ips.ac.ruKinetics of DME synthesis by methanol dehydration or directly by syngas processing wasstudied. Kinetic schemes of the process mechanism were obtained based on independentinformation, involving novel stages in transformations of strongly adsorbed species. Kineticmodels and computer simulations were obtained on the basis of these schemes, whichcorrelate with experimental results satisfactorily. It was shown that syngas of any compositionis suitable for DME synthesis up to H 2 :CO=1:1, including "lean" gas.Dimethyl ether (DME) synthesis from syngas is comprised from three simultaneousreactions (macrostages): methanol synthesis (1), methanol dehydration (2), water gas shiftreaction, or WGSR (3):СО 2 + 3Н 2 = СН 3 ОН + Н 2 О (1)2СН 3 ОН = (СН 3 ) 2 О + Н 2 О (2)СО + Н 2 О = СО 2 + Н 2 (3)Accordingly, a catalyst for direct DME synthesis should be highly active in all threereactions.Kinetics of methanol synthesis coupled with its concurrent reaction, WGSR, is studiedquite well. One of the goals of this work was the study of methanol dehydration into DMEConversion of СН 3ОН, %807060504030201000,0 0,2 0,4Contact Time, s531462over γ-Al 2 O 3 in a wide range of experimentalconditions with the view to obtain a kineticmodel of this reaction and finally to describethe system of reactions above. For this, 6commercial alumina samples were tested(Fig.1); the best sample was used for kineticstudies under 0.1 MPa. It is seen that aluminaprovided by different companies is verydifferent in activity.Fig.1. Contact time dependence of methanolconversion over different γ-Al 2 O 3 batches 1-6(260 o C, 0.1MPa, СН 3 ОН/N 2 = 1/1).358