Hydrogen Recovery Via Nanoporous Carbon Membrane for Large Scale Refinery Application

Hydrogen recovery from refinery off-gas offers a cost-effective and environmentally friendly alternative to meet the projected growth in hydrogen demand in refineries. Although a unique membrane-based process was demonstrated to be technically feasible in the past, several product- and process-related barriers have prevented its field implementation. This project will develop a nanoporous carbon molecular sieve membrane that can overcome the product-related barriers. An in-line regeneration technique will be employed to solve the process-related barriers. Hydrogen recovery efficiency will be improved through a membrane structure tailored for these applications. Phase I demonstrated significant hydrogen recovery from binary streams ¿ containing hydrogen/hydrocarbons or CO ¿ selected to simulate refinery waste streams and pressure swing adsorption (PSA) purge streams. After aging/fouling, the membranes were restored via in situ regeneration. An economic analysis demonstrated the feasibility of a payback period less than one year. Phase II will focus on product optimization and process development, in order to demonstrate the proposed hydrogen enrichment process. Then, the optimized process will be demonstrated in a bench-top experiment and verified with a mathematical simulation. Long term performance stability will be confirmed by testing the prototype in a slip stream in the field. Finally, a full-scale module will be fabricated for field testing in Phase III. Commercial Applications and other Benefits as described by the awardee: The hydrogen recovery technology should achive significant energy savings and CO2 reduction in refinery applications. Other applications include the recovery of residual chemicals from waste streams, following bulk separations in chemical production processes