This project will develop an innovative, effective, and economic process for high temperature, high pressure gas cleanup. This will promote the cost effective utilization of domestic coal reserves. This objective will be achieved by the development of a novel carbon molecular sieve-ceramic composite membrane. The unique chemical and physical properties of carbon molecular sieves formed interstitially in a macroporous ceramic support offers the potential of facile incorporation into existing ceramic membrane-based particulate removal systems to provide relatively clean, concentrated hydrogen from hot coal gas. Membrane separations for gaseous mixtures have become wide spread since the development of asymmetric polymer membranes over the last three decades. This is because of the relatively low operating costs for a membrane-based gas separation process. Utilization has been limited to low temperature systems, however, because of the lack of membrane systems capable of withstanding high temperatures. A number of ceramic membranes, capable of withstanding high temperatures, have been developed in the last few years, but they are not suitable for gas separations because the channels they contain are too large to separate gas molecules. In this project an organized carbon structure will be formed inside of the channels of one of the commercially successful ceramic membranes. The deposited carbon will act like a sieve to selectively pass hydrogen molecules while rejecting larger molecules. The process for making these membranes promises to be inexpensive. One of the many possible applications of such a membrane is the conversion of coal to gaseous fuels in a manner which would allow an economical separation of sulfur compounds from the final product.