Haber, << HAH buhr, >> process is a commercial method of producing ammonia from nitrogen and hydrogen. Fritz Haber, a German chemist, developed the process and demonstrated it in 1909. He patented it in 1910. Another German chemist, Carl Bosch, later adapted the process for industrial use. It is also called the Haber-Bosch process.
In the Haber process, three parts of hydrogen unite with one part of nitrogen to form ammonia. The process takes place at about 550 °C and at 200 to 250 times atmospheric pressure. The nitrogen and hydrogen combine at the surface of a solid catalyst, a substance that speeds up the reaction. It consists mainly of iron, with small amounts of alumina and potassium oxide. All the hydrogen and nitrogen do not combine. The uncombined gases are recirculated through the process.
Almost all modern ammonia plants use the Haber process or variations of it. Most early ammonia plants that used the Haber method obtained hydrogen from water gas and nitrogen from producer gas. Water gas and producer gas are made from hot coke (see Gas (How gas is manufactured) ). Today, many ammonia plants obtain hydrogen and nitrogen from other sources. Hydrogen may be obtained from natural gas, and nitrogen may come from the distillation of liquid air (see Liquid air ). Other modifications of the Haber process include changes in the composition of the catalyst and in the temperature and pressure used.
