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At the present time,H2S is the byproduct of the process of coal coking,petroleum extraction,and petroleum refining.Industrial gases,such as natural gas,biogas and Claus tail,often contain high concentration of H2S,which is harmful to the environment and human being.When H2S is oxidized into SO2,it will become the source of the acid rain.Meanwhile,the exhaust gas to the air must be meet the limit of regulation which is to low the concentration to the permission level of 10ppm[1].Recently,some adsorbents[2-4] are prepared by impregnating or grafting methods.SBA-15 and MCM-41 are often selected to be a carrier because of their porous ordered structure.And chemical compounds with amine group are the modifier.The adsorbents can remove H2S at low temperature with higher capacity.Many studies have being reported about the removal of H2S (<5000ppm) using amine-modified adsorbents,but the investigation about removal of high concentration of H2S (>5000ppm) is not common.A novel adsorbent was prepared by modifying the MCM-41mesoporous molecular sieves with tetraethylene pentamine (TEPA).It was used to remove high concentration H2S (1.62v%) at low temperature.The adsorption performance of H2S was examined by dynamic breakthrough experiments.The effects of loading amount of TEPA,adsorption temperature and space velocity on the breakthrough capacity were studied.And the performance of TEPA-modified MCM-41 was compared with that of the commercial cocoanut activated carbon.The results show that,at 30℃,799.92h-1,the loading of 60wt% TEPA modified adsorbent has the best breakthrough capacity of H2S,reach up to 168.62mg H2S /g ads.At 30℃,259.98h-1,the breakthrough capacity of 60wt% TEPA-modified MCM-41 is 8.05 times that of activated carbon.