What is understood by ‘Hydrogen economy.’
Hydrogen is required for the synthesis of a number of industrial products and thus, affects the economy of a country. For example:
(i) Synthesis of ammonia: A mixture ofN2 and H2 in the ratio of 1:3 compressed to 200 atmospheres and heated to 673 K in the presence of a catalyst is used for the manufacture of ammonia in Haber's process.
(ii) Hydrogenation of oils: Hydrogen is used in the hydrogenation of edible oils (unsaturated in nature) to form solid fats for the production of vegetable ghee.
(iii) Manufacture of methyl alcohol: Water gas enriched with H2 is compressed to 200 atmospheres and is then passed over catalyst mixture of ZnO and Cr2O3 at 573K to form methyl alcohol.
(iv) Oxy-hydrogen flame. When hydrogen is burnt in oxygen heat is liberated. This heat is used in cutting as well as welding of metals. The apparatus in which heat is produced is called an oxy-hydrogen torch. Atomic hydrogen torch used for the same purpose employs atomic hydrogen.
(v) Synthetic petrol: Hydrogen is used as a constituent of synthetic petrol. It is formed by, passing hydrogen into a paste of powdered coal in crude oil by using a suitable catalyst.
