Dual-enhanced steam methane reforming by membrane separation of H2 and reactive sorption of CO2

This study proposes a dual-enhanced steam methane reforming (SMR) method for hydrogen production with simultaneous H-2 membrane separation and CO2 sorption. Thermodynamic calculations and experimental studies were carried out to study the effectiveness of the dual-enhanced. Theoretically, dual-enhanced SMR was found to decrease the reaction temperature to 500 degrees C with a CH4 conversion of 86.2% under the H-2 separation ratio of 0.6 and CO2 sorption ratio of 0.95, in contrast, the CH4 conversion was 52.1% under the same conditions but without any enhancement, thus lowering energy consumption by using dual-enhanced steam reforming. A palladium membrane tube was prepared by electroless plating and used for membrane separation of H-2. A fixed-bed reactor packed with complex catalyst containing nano-Ca as CO2 sorbent and NiO/Al2O3 as reforming catalyst was assembled. Experimental results indicated that with a lowered reaction temperature to 500 degrees C, the CH4 conversion can be 62.6%. The conversion of CH4 by dual-enhanced SMR was 27.2%, higher than that obtained by conventional SMR at a reaction temperature of 600 degrees C and a steam-to-methane (S/M) molar ratio of 4. Product gas with 98.1% H-2 was directly obtained by dual-enhanced SMR. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.