Rhodium-based catalysts in ionic liquids have been used for the hydrogenation of propene in a reactor composed of thin layers of catalyst solution supported on or in corrugated polymer sheets operated in a cross-corrugated configuration. The effect of the number of corrugated sheets and of reactant gas flow rate is described. Conversions to propane of up to 95% have been demonstrated and reactor performance has been maintained over hundreds of hours of operation. The catalyst-membrane system based on rhodium(I)-[bmim]PF6-PESC was found to be remarkably robust, retaining high levels of activity after removal from the reactor, storage in air for 3 months and re-introduction into the reactor.