Mesoporous-molecular-sieve-supported polymer sorbents for removing H2S from hydrogen gas streams

A series of sorbents with a linear polyethylenimine (PEI) supported on the mesoporous molecular sieves, including MCM-41, MCM-48 and SBA-15, have been prepared and used to remove H(2)S from a model gas containing 0.40 v% of H(2)S and 20 v% H(2) in N(2) gas. The sorption was conducted in a fixed-bed system at a temperature range of 22-75 C, a GHSV range of 337-1,011 h(-1) and atmospheric pressure. The effects of the operating temperature, GHSV, the amount of PEI loading and the different molecular sieve supports were studied. A reduction in the temperature and GHSV improves the sorption performance of the supported PEI sorbents. A synergetic effect of the SBA-15 support and PEI on the H(2)S sorption performance was observed. Loading 50 wt% PEI on SBA-15 gave the best breakthrough capacity, while loading 65 wt% PEI on SBA-15 had the highest saturation capacity. The mesoporous molecular sieve with large pore size and three-dimensional channel structure favors increasing the kinetic capacity of the supported PEI sorbent. In addition, the developed sorbents can be regenerated easily at mild conditions (temperature range of 75-100 C) and have excellent regenerability and stability. The results indicate that the mesoporous-molecular-sieve-supported polymer sorbents are promising for removing H(2)S from hydrogen gas streams.