*** 96-61267 Ji . This proposal addresses development of cost-effective, highly selective, high-pressure, and high-temperature gas separation modules by use of low-cost, highly compact ceramic ultrafiltration (UF) modules as gas separation membrane supports. The active separation layer will be a thin ceramic membrane with pore size of 4- 10 nm modified with silver or copper ions and sealed with a poly(dimethylsiloxane) (PDMS) thin film.. During Phase I, novel facilitated transport organic-inorganic membranes will be developed. High selectivity of these membranes for olefin/paraffin separation will be demonstrated. A reservoir method will be employed to modify the top thin membrane of a ceramic module with silver or copper ions. An innovative method will be used to apply a thin PDMS film to the modified ceramic membrane to form a dense separation layer. These membranes will be tested at temperatures ranging from 25 to 200 C for separation of olefin/paraffin mixtures at a laboratory scale. The novel high-pressure and high-temperature facilitated transport membrane modules to be developed in this program, if successfully scaled up to production-scale ceramic modules (as envisioned for Phase II work), would be a key element in the separation of olefin/paraffin mixture in the chemical and petrochemical industry. They could also be used to effectively separate carbon monoxide from a synthesis gas. ***