GB293077A - Improved metallic apparatus for carrying out chemical and other processes - Google Patents

Abstract

293,077. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). March 3, 1927. Retorts.-Apparatus for carrying out processes such as the heat treatment of coal, particularly at high temperatures and pressures with gases, liquids, &c., containing hydrogen, oxygen, 'or sulphur is made of iron particularly free from impurities. The degree of purity must be such that the iron shows under the microscope no corrosion at the boundaries of the grains after treatment at a high temperature with gases or liquids containing oxygen or sulphur and preferably in presence of hydrogen. The requisite degree of purity may be obtained by subjecting iron, at high temperatures and under conditions precluding oxidation, to the action of gases which form gaseous compounds with the impurities (oxygen, sulphur, carbon &c.). For example mild steel may be treated with hydrogen at 900' C., or with a weakly oxidizing mixture of hydrogen-water vapour at 550-600‹ C. and 150 atmospheres. The apparatus may be further protected with a coating of resistant material such as chromium tungsten, uranium, manganese, aluminium, silver, copper, enamel &c. Specification 275,662 [Class 32, Distilling &c.] is referred to.