High temperature hydrogen sulfide adsorption on activated carbon II. Effects of gas temperature, gas pressure and sorbent regeneration

Several types of activated carbon sorbents were evaluated for removal of H2S at high temperatures (400-600 degrees C) in an integrated gasification combined cycle (IGCC) power generation process. Part I of this series of papers discussed the effects of gas composition and metal addition. Here we examine the effects of gas temperature, gas pressure and sorbent regeneration. Adsorption experiments with a zinc-impregnated activated carbon sample produced almost identical breakthrough times at varied temperatures (400-600 degrees C). High pressure (10 atm) adsorption experiments showed significantly longer breakthrough times at 10 atm compared to 1 atm. Gaseous H-2 sample regeneration was found to be the most effective regeneration method of the variety of methods analyzed, with all previously H2S adsorbed sulfur being removed in a H-2 regeneration experiment. While additional research is necessary to further evaluate sample regeneration and multi-cycle adsorption/regeneration, results of temperature and pressure effect experiments are encouraging for IGCC applications. (C) 2000 Elsevier Science Ltd. All rights reserved.