Methanol synthesis, membrane reactors

Struis and Stuck [6.12] have evaluated the application of membrane reactors for methanol synthesis using methanol permselective Nafion membranes. In their design calculations they utilize kinetic and membrane permeation data measured in their laboratory. They estimate that with 10 im thin membrane under methanol synthesis plant technically relevant conditions (T = 200 C, P = 40 bar, GHSV = 5000 h ), the single pass reactor yield improves by 40 %, and that the additional costs for the membrane materials correspond only to two production months. The ability of the Nafion membranes to withstand such conditions for prolonged periods still remains, however, questionable. 

Struis RPWJ and Stuck S. Verification of the membrane reactor concept for the methanol synthesis. Appl Catal A Gen 2001 216(1-2) 117-129. 

MTBE synthesis from /-butanol and methanol in a membrane reactor has been reported by Salomon et al. [2.453]. Hydrophilic zeolite membranes (mordenite or NaA) were employed to selectively remove water from the reaction atmosphere during the gas-phase synthesis of MTBE. This reaction was carried out over a bed of Amberlyst 15 catalyst packed in the inside of a zeolite tubular membrane. Prior to reaction, the zeolite membranes were characterized by measuring their performance in the separation of the equilibrium mixture containing water, methanol, /-butanol, MTBE, and isobutene. The results obtained with zeolite membrane reactors were compared with those of a fixed-bed reactor (FBR) under the same operating conditions. MTBE yields obtained with the PBMR at 334 K reached 67.6 %, under conditions, where the equilibrium value without product removal (FBR) would be 60.9%. 

Membrane catalysts use a polymeric support. Polymer composites based on PPE as polymeric support with HPAs are used as a catalysts. The HPA-polymer composites are prepared by blending HEA with the polymer in a methanol/chloroform solvent mixture. These composites are active in the synthesis of tert-butyl alcohol, ethyl tert-butyl ether and in some reactions involving ethanol and MTBE. A PPE-based membrane reactor showed the best performance, among some other polymer membranes tested. 

GaUucci F, Basile A. A theoretical analysis of methanol synthesis from CO2 and in a ceramic membrane reactor. Int J Hydrogen Energy 2007 132 5050-5058. 

Verification of the Membrane Reactor Concept for the Methanol Synthesis. 

M. H. Khademi, M. R. Rahimpour and A. Jahanmiri, Differential evolution (DE) strategy for optimization of hydrogen production, cyclohexane dehydrogenation and methanol synthesis in a hydrogen-permselective membrane thermally coupled reactor, Int. J. Hydrogen Energy, 2010, 35, 1936-1950. 

Khademi, M.H., Jahanmiri, A. and Rahimpour, M.R. (2009) A novel configuration for hydrogen production from coupling of methanol and benzene synthesis in a hydrogen-permselective membrane reactor. International Journal of Hydrogen Energy, 34 (12), 5091-5107. 

Assabumrungrat S, Phongpatthanapanich J, Praserthdam P, Tagawa T and Goto S (2003), Theoretical study on the synthesis of methyl acetate from methanol and acetic add in pervaporation membrane reactors effect of continuous-flow modes , Chem EngJ, 95,57-65. 

Rahimpour MR, Bayat M, Rahmani F Dynamic simulation of a cascade fluidized-bed membrane reactor in the presence of long-term catalyst deactivation for methanol synthesis, Chem Eng Set 65 4239—4249, 2010. 

Rahimpour, M.R., Rahmani, F. and Bayat, M. (2010) Contribution to emission reduction of CO2 by a fluidized-bed membrane dual-type reactor in methanol synthesis process. Chemical Engineering and Processing Process Intensification, 49, 589-598. 

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