| Hydrogen sulfide as a main pollutants of the atmosphere, is a kind of mephitic gas with rotten-egged odor, and it can seriously endanger humans health. Metals are likely to be eroded by it so that it can cause equipments and pipelines corrosion and poison industrial catalyst. Industrial exhaust that contains small amounts of hydrogen sulfide can pollute the air terribly, sometimes a lot of resources are abandoned because of the presence of low concentration of hydrogen sulfide. So, to reduce hydrogen sulfide gas concentration to a few ppm becomes an important issue that should be solved as soon as possible. In this study, we choose SBA-15 as a support, with different modifications, to develop efficient adsorbents for low-concentration hydrogen sulfide gas removal.The contents of the job are listed as follows:1.The synthesis of the mesoporous molecular sieve SBA-15:hydrothermal synthesis method was applied to prepare SBA-15 by using TEOS as silicate material and triblock copolymer P123 as the template in the acidic condition. The SBA-15 was characterized by XRD,FT-IR, and BET techniques.The pore diameter of SBA-15 was 9.6 nm,specific surface area was 588.5m2/g,pore volume was 1.203 cm3/g.2.The study on adsorbents modified with alkaline materials and PEI.SBA-15 mesoporous material was modified with sodium carbonate, sodium bicarbonate, potassium carbonate and PEI, and their adsorption performanece on hydrogen sulfide were investigated. The results showed that adsorbents modified with alkaline materials had a bad adsorption capacity on hydrogen sulfide. The PEI loading quality had an optimum value when the adsorbents showed a best adsorption performance.3. The study on adsorbents modified with different transition metals.SBA-15 mesoporous material was modified with Zn,Fe,Mn,Cu,Co and Ni,Results showed that adsorbents modified with zinc has the best adsorption properties on hydrogen sulfide, and the best ratio of zinc was wt23%.Meanwhile, the affects of doping different metals in Zn/SBA-15 were investigated, results showed that doping copper enhanced the adsorption property of Zn/SBA-15, on the contrary doping magnesium reduced he adsorption property of Zn/SBA-15.4.The study on Zn/SBA-15 of hydrogen sulfide adsorption. The effect of the gas concentration, gas flow rate, adsorption temperature, the affects of the exit of carbon dioxide and oxygen are investigated. Results showed that the adsorption property reduced when increasing the feed gas velocity. At a range of 288-573 K, the adsorption capacity presented first decreasing and then increase trend. With increasing inlet H2S concentration, the breakthrough capacity increased, and the existence of CO2 and O2 made a disadvantage on the adsorption capacity of H2S on Zn/SBA-15.5.Researched the adsprption mechanism of Zn/SBA-15 on hydrogy sulfide, hydrogy sulfide diffused into the pore canal of the mesoporous materials, and react with the zinc oxide with loaded on the surface of SBA-15 to form zinc sulfide. We also studied the regeneration capacity of Zn/SBA-15, results showed that the adsorbent could be recycled for four times at 573 K under the air condition, and the breakthrough capacity did not changed.
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