Industrial & Engineering Chemistry Research, Vol.54, No.2, 612-622, 2015
Kinetic Study of Hydrogen Production by the High Temperature Water Gas Shift Reaction of Reformate Gas in Conventional and Membrane Packed Bed Reactors over Ca-Promoted CeO2-ZrO2 Supported Ni-Cu Catalyst
The kinetics of the high temperature water gas shift (HTWGS) reaction was performed in a hydrogen selective membrane reactor (MR) and compared with that in a packed bed tubular reactor (PBTR) at a pressure range of 150-250 psi, temperature range of 400-500 degrees C and weight of catalyst/CO molar flow rate ratio of 1.1-2.7 (g-cat.hr)/mol using reformate gas over a Ni-Cu catalyst on Ca-promoted CeO2-ZrO2 support. The purpose was to estimate the effect of hydrogen removal on conversion and reaction products yield. The characteristics and hydrogen permeation properties of the MR were also studied. The activation energy obtained for the reaction in the PBTR was 190 kJ/mol, whereas the MR exhibited activation energy of ca. 50% lower than the PBTR. MR characterization results showed that hydrogen permeation and recovery increased with temperature and trans-membrane pressure, which could be correlated using Sieverts law to yield an activation energy of 22.7 kJ/mol.