The objectives of this project were twofold. The primary objective was to demonstrate the concept of using reactive ion exchange membranes (IEMs) containing organic amines for the separation of CO/sub 2/ and H/sub 2/S from coal gasification product gases. The potential advantage of this approach, known as facilitated transport, is to improve the selectivity of membrane separations without sacrificing high fluxes. A more fundamental objective was to investigate the mechanism of transport in ion exchange membranes. The facilitated transport of CO/sub 2/ and H/sub 2/S was studied using ion exchange membranes containing cations of ethylene diamine (EDA). Steady-state fluxes were measured for CO/sub 2/ and H/sub 2/S from single component gas streams, binary mixtures of CO/sub 2/ and H/sub 2/S with CH/sub 4/, CO/sub 2//H/sub 2/S binary mixtures, and ternary mixtures containing CO/sub 2//H/sub 2/S/CH/sub 4/. Fluxes were measured with and without EDA present as a function of feed gas composition. Diffusion coefficients were determined for H/sub 2/S, CO/sub 2/, and the EDA and gas complexes. A set of reaction and transport properties were collected from laboratory measurements and an extensive literature survey. The IEM separation factors compare very well with those for commercial membrane gas separation processes. Analytical models derived to predict the single component H/sub 2/S and CO/sub 2/ facilitation factors showed excellent agreement with experimental data. The importance of this project is that we have demonstrated experimentally that a reactive ion exchange membrane can be highly selective for CO/sub 2/ and H/sub 2/S over CH/sub 4/ and still have high fluxes. In addition, our understanding of the transport mechanisms involved has enabled us to simulate our experimental data theoretically, which is necessary for scaleup and design. 57 refs.