Abstract: A desulfurization process includes desulfurizing a hydrocarbon fuel using a desulfurizing agent including a support, nickel sulfide on the support, and zinc oxide. The desulfurizing agent is heated to 250° C. or more.

Abstract: An adsorbent for removing sulfur compounds from sulfur compounds-containing fuel gas contains a zeolite ion-exchanged with Ag and has an excellent performance when used to remove sulfur compounds from the fuel gas, irrespective of the moisture concentration in the fuel gas, and a method for removing sulfur compounds from sulfur compounds-containing fuel gas by use of an adsorbent of the above-mentioned type. The zeolite is a Na—+Y type zeolite.

Abstract: An adsorbent for removing sulfur compounds from sulfur compounds-containing fuel gas contains a zeolite ion-exchanged with Ag and has an excellent performance when used to remove sulfur compounds from the fuel gas, irrespective of the moisture concentration in the fuel gas, and a method for removing sulfur compounds from sulfur compounds-containing fuel gas by use of an adsorbent of the above-mentioned type. The zeolite is a Na—Y type zeolite.

Abstract: An adsorbent for removing sulfur compounds from sulfur compounds-containing fuel gas comprises a zeolite ion-exchanged one or more transition metals selected from the group of Ag, Cu, Zn, Fe, Co and Ni and has an excellent performance when used to remove the sulfur compound from the fuel gas irrespective of a moisture concentration in the fuel gas, and a method for removing sulfur compounds from sulfur compounds-containing fuel gas by use of an adsorbent of the above-mentioned type. The zeolite is favorably made of an X type zeolite, a Y type zeolite or a &bgr; type zeolite.

Abstract: A method of purifying NOx-containing exhaust gases characterized by using ammonium acetate as a reducing agent with a zeolite-based catalyst. NO.sub.x in NO.sub.x -containing exhaust gases can be removed extremely effectively even at a low concentration thereof by using Fe-treated mordenite as a zeolite-based catalyst according to said method, and since it uses ammonium acetate as a reducing agent, an excellent effect free from ammonia leakage can be obtained. Particularly NO.sub.x in NO.sub.x -containing exhaust gases can be removed effectively at and around a discharge temperature of an exhaust gas from a gas engine in the presence of ammonium acetate as a reducing agent by constituting Fe-containing mordenite as a monolithic material. Hence, it makes it possible to obtain an excellent effect of simplifying the whole denitration system without needing temperature control of an exhaust gas and/or a catalyst bed. In addition, the NO.sub.