Pd-based composite membrane and its high-pressure module for pre-combustion CO2 capture

This study investigates configuration of a module for withstanding high pressure and temperature for CO2 capture from a coal gasifier. In order to increase the durability of the module at high pressure and temperature, a flange-type unit-cell module was installed in a high-pressure chamber. Hydrogen permeation and N-2 leakage tests showed that H-2/N-2 selectivity remained at similar to 4000 after similar to 300 h at a pressure difference of 2000 kPa (similar to 20 bar) and 673 K. A CO2 capturing test was carried out at 673 K and a pressure difference of 2000 kPa with a 40% CO2 + 60% H-2 feed gas mixture, which is similar to the composition in a coal gasifier after shift reaction and H2O removal. It was shown that CO2 could be enriched up to 78-95% with a hydrogen recovery ratio of 82-97% when the feed flow rate was 0.05-0.17 Nm(3) h(-1) with a membrane surface area of 16.6 cm(2). (C) 2013 Elsevier Ltd. All rights reserved.