Pure hydrogen from the dry gas of refineries via a novel pressure swing adsorption process

Dry gas of refineries is an important source of cheap hydrogen for PEMFC vehicles if an efficient separation/purification technology is available. Presented is a novel pressure swing adsorption (PSA) technology that features in uncoupling of the columns in terms of pressure equalization of the buffer tanks and a new cycling sequence of operating steps. Hydrogen enriching tests from a simulated dry gas using two combinations of adsorbents were used to find the appropriate operating conditions for the new process and to examine its performance at low operating pressures. The operation flexibility and high productivity of the new PSA process operating at low pressures were experimentally demonstrated. Hydrogen with a purity of 99.99% could be produced with relatively high recovery at pressures lower than 1.0 MPa.