The recovery by carbon molecular sieve membranes of hydrogen transmitted in natural gas networks

The recovery of hydrogen from gas mixtures with hydrocarbons may provide a commercial niche for carbon molecular sieve membranes. A potential application is the recovery of hydrogen transmitted with natural gas in a mixed network in a hydrogen economy scenario. Performance data measured on the bench-scale were applied to a techno-economic evaluation of hydrogen recovery and the results were compared to a commercial polyimide membrane's performance. The carbon membranes produced higher purity hydrogen, consumed less energy in separation and achieved competitive specific separation costs under certain conditions. Recovery of 90% of the hydrogen from a feed stream containing 5 mol% hydrogen was feasible in a single stage.