Production of hydrogen from hydrogen sulfide reformation in the presence of benzene

Experimental results presented here are on the reformation of hydrogen sulfide in the presence of trace amounts of benzene as impurity to hydrogen and sulfur. These results are aimed at providing an alternative to the Claus process to recover chemical energy and pure high value sulfur from the acid gas. The reformation of H₂S in the presence of hydrocarbon impurities to hydrogen fuel and pure sulfur offers promising alternative route for the treatment of acid gases extracted from gas wells that contains hydrocarbons and other impurities. The effect of temperature and composition of inlet gas stream having a mixture of hydrogen sulfide and benzene diluted in nitrogen were experimentally examined using a laboratory-scale quartz tubular reactor. The role of reactor temperature on the decomposition of hydrogen sulfide as well as the decomposition of benzene to produce hydrogen are shown. The results showed that at temperatures exceeding 1323K the production of hydrogen increased vividly with complete decomposition of benzene that also provided increased conversion of hydrogen sulfide. Complete consumption of benzene was achieved at relatively low temperatures of 1373K. The results showed increased destruction of hydrogen sulfide in the presence of benzene compared to dissociation of hydrogen sulfide in absence of benzene. Carbon disulfide formation during the reformation of hydrogen sulfide in presence of benzene was inevitable and it increased with increase in temperature. A new means to maneuver CS₂ formation and carbon laydown was evaluated by changing the carbon constituent in the inlet feed gas stream. These results provide favorable reactor operational conditions to reform hydrogen sulfide in the presence of benzene without increasing the formation of CS₂. The results also provide a new treatment method for hydrogen sulfide stream contaminated with benzene.