Abstract: This invention provides a catalyst for producing hydrogen gas from a mixed gas comprising dimethyl ether and water vapor or carbon dioxide gas, which comprises copper, iron, cobalt, palladium, iridium, platinum, rhodium, or nickel as an active component, and a method of producing synthesis gas or hydrogen gas in a high yield at a low temperature. By using the catalyst, fuel cell, electricity generation, reduction of iron ore and the like can be carried out.

Abstract: This invention provides a catalyst for producing hydrogen gas from a mixed gas comprising dimethyl ether and water vapor or carbon dioxide gas, which comprises copper, iron, cobalt, palladium, iridium, platinum, rhodium, or nickel as an active component, and a method of producing synthesis gas or hydrogen gas in a high yield at a low temperature. By using the catalyst, a fuel cell, electricity generation, reduction of iron ore and the like can be carried out.

Abstract: Powder and/or fine particles containing mainly oxides of iron or ferroalloys, which are used or generated in ironworks, steelworks, etc. are sieved to a grain size range between about 32 mesh and about 10mm and used as reduction catalyzer. A reactor is filled with said reduction catalyzer. Exhaust gas containing nitrogen oxides and with added ammonia is passed in contact with said reduction catalyzer through said reactor, while heating said reduction catalyzer to a temperature between about 300.degree. C and about 370.degree. C, whereby nitrogen oxides are removed from said exhaust gas by reduction. Said reduction catalyzer can be used as material for ironmaking, without requiring any further treatment, after use as catalyzer.