Production of fuel-cell grade hydrogen by thermal swing sorption enhanced reaction concept

The performance of a novel thermal swing sorption enhanced reaction (TSSER) concept for production of fuel-cell grade hydrogen (<20ppmCO) by low temperature (∼490∘C) catalytic steam–methane reforming (SMR) is simulated. The process simultaneously carries out the SMR reaction and removal of CO2CO2 from the reaction zone by chemisorption on K2CO3K2CO3 promoted hydrotalcite in a single unit. The chemisorbent is periodically regenerated by steam purge at ∼590∘C. The concept efficiently utilizes the CO2CO2 sorption capacity of the chemisorbent and requires a relatively low amount of steam for its regeneration. A compact, small foot-print H2H2 generator can be designed for a residential or industrial hydrogen fuel-cell unit by the concept.Recently measured equilibrium isotherms and column dynamics for ad(de)sorption of CO2CO2 on the chemisorbent are reviewed and parametric evaluations of design variables like catalyst:sorbent ratio and feed gas conditions (pressure, temperature, and H2O:CH4H2O:CH4 ratio) are carried out.