Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

OP-3-11DEMANDS FOR CATALYSTS SUITABLE FOR A WGS MEMBRANEREACTOR WITH GAS FEED FROM GASIFIERSKrzysztof Gosiewski, Marek TanczykInstitute of Chemical Engineering, Polish Academy of Sciences, Gliwice, PolandA conventional WGS plant consists of two-stage process with the hightemperature reactor followed by the cooler and the low temperature reactor. Theconventional reactor is usually fed with a gas with relatively high H 2 /CO ratio (2 to 5),while for processing of coal-derived or biomass gasification gas H 2 /CO is around 0.5and rarely exceeds 1. Thus, the total adiabatic temperature rise in WGS reactor forsuch a feed gas is much higher than that when WGS reactor is fed with syngas fromSR or POX. For membrane reactor (MR) the single-stage tube in tube or multi-tubularconfiguration is usually proposed. The tube and shell zone in the MR are separatedby a membrane. In conventional plants the total temperature rise not exceeding300 °C can be adjusted using 2 separate stages, usually from 300 to 500 °C for hightemperature catalyst and from 180 to 280 °C for low temperature catalyst.Mathematical simulations of the MRs with H 2 selective membranes were done toestimate operating conditions for industrial application of MR with coal-derived gasfeed. It was found that for MR the temperature rise in the reaction zone can be ashigh as 350 °C for S/C ratio below 2.0. Existing commercial catalysts will not survive,however, such a temperature rise cf. [1]. Thus, a catalyst with operationaltemperature range of 200 – 600 °C is expected as a reasearch target for 2015 [2].To adjust the temperature in MR to the present catalyst operation range aneconomically not attractive high S/C ratio should be applied. On the other hand, heatexchange to the cold sweep gas becomes to be very important. A discussion of coalderivedgas processing in MRs at pressures up to 2.6 MPa is given. Finally, it isconcluded that the future of the WGS membrane technology will depend on thedevelopment of new catalysts with adequately wide range of operating temperatures.References:[1]. L. Lefferts, (project leader), Project: Water-gas-shift reaction in a catalytic membrane reactor forfuel-cell application Faculty of Science and Technology - University of Twente (2003 – 2007).[2]. T.H. Vanderspurt, IV.C.9 Advanced Water-Gas-Shift Membrane Reactor, DOE HydrogenProgram (2005), p. 199.Acknowledgements. Financial support from the Polish Ministry of Science and HigherEducation (Project PBZ-MEiN-2/2/2006) is gratefully acknowledged.79