Chemical Engineering & Technology, Vol.35, No.3, 539-546, 2012
Hydrogen Production Integrated with Simultaneous CO2 Sequestration on Fly Ashes from Power Plants
Integration of chemical reactions with in situ adsorptive separation of one of the reaction products helps to improve the reactant conversion or/and product selectivity. In the steam-methane reforming (SMR) process, despite a reversibility of employed reactions, the in situ adsorption of CO2 enables an almost total conversion of methane and produced CO, so pure hydrogen can be obtained directly from a single-step adsorptive reactor. However, the main problem in practical application of such integrated process is a saturation of sorbent with CO2 and the need of its cyclic regeneration. A series of experiments to determine the kinetics for CO2 sorption on fly ashes were performed under operating conditions usually applied for the sorption-enhanced SMR process and the possible CO2 uptake was estimated. The obtained results indicate that fly ashes can be utilized as an efficient and cheap sorbent for the considered hydrogen production process.