(130g) The Use of Membranes to Lower the Cost of Hydrogen Production With Concurrent Carbon Dioxide Sequestration

Methods of producing fuel and electric power without concurrently emitting carbon dioxide to the atmosphere are being sought.  One approach is to produce syngas (carbon monoxide and hydrogen) from coal or natural gas, convert the carbon monoxide to carbon dioxide through the water gas shift (WGS) reaction, producing carbon dioxide and more hydrogen, and then separate the resulting carbon dioxide/hydrogen mixture.  The separated carbon dioxide can be sequestered underground.

This process is the basis of the proposed hydrogen economy.  A key issue in this scheme is the hydrogen/carbon dioxide separation step.  Currently, most process developers use the Selexol process (carbon dioxide absorption into cold oligomers of ethylene glycol), which is a safe but expensive choice.  This paper describes the development of new carbon dioxide/hydrogen- and hydrogen/carbon dioxide-selective membranes that can be used to simultaneously sequester carbon dioxide and provide a high quality hydrogen fuel.  Very significant cost savings can be achieved. The technology is at the bench/pilot plant stage.