Novel thermal swing sorption enhanced reaction process for simultaneous production of fuel-cell grade H₂ and compressed CO₂ from synthesis gas

Synthesis gas produced from coal gasification can be used to produce hydrogen through water gas shift (WGS) reaction and purification procedures. A study on the Thermal Swing Sorption Enhanced Reaction that simultaneously carries out the WGS reaction and the separation of CO₂ from the reaction zone by using a novel CO₂ chemisorbent in a single unit operation was carried out. The new process produced a fuel-cell grade hydrogen and compressed CO₂ as a by-product gas. The simultaneous removal of CO₂ during WGS reaction circumvented the thermodynamic limitation and shifted equilibrium to the right resulting in the enhancement of the extent of the forward reaction. Thus, a pure hydrogen stream could be directly produced, and the process is simpler and potentially more economical than the conventional WGS. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).