Experimental and Simulation Studies of Effects of
Operating Conditions and Membrane Properties on the Performance of Zeolite
Membrane Reactors for High Temperature Water Gas Shift Reaction
Seok-Jhin Kim, Shaowei Yang, Junhang Dong
Department of Chemical & Materials Engineering,
University of Cincinnati, Cincinnati, OH 45220, USA
ABSTRACT
Modified microporous
MFI-type zeolite membranes have been studied as high temperature water gas
shift (WGS) membrane reactors (MR) using a cerium-doped ferrite (Fe/Ce) catalyst. The effects of the reaction conditions and
the membrane separation properties on the CO-conversion (cCO)
in the MR were investigated experimentally and by simulations using a simple one-dimensional
model which was validated by the experimental data. The experimental results
have demonstrated that the zeolite MRs with moderate H2 separation
performance are capable of overcoming the equilibrium CO-conversion (cCO,e) existing in traditional packed-bed reactors at
operating temperatures of >500oC where CO reaction rate is rapid
enough to effectively minimize the permeation of the unreacted CO. The model
calculations have shown that near-completion CO-conversion (cCO>99.5%)
may be achieved under realistic operating temperature, pressure, space velocity
and catalyst load even for membranes with moderate H2 selectivity,
e.g. (aH2/CO2<50)
and H2permeance (<3×10-7mol/s·m2·Pa).