The Alkali Industry

Abstract

IN the Hurter Memorial Lecture to the Society of Chemical Industry (Chemistry and Industry, 54, 121; 1935), Dr. J. T. Conroy gave a very interesting review of the development of the manufacture of sulphuric acid, alkali, chlorine and allied products since about 1890. This period has seen the disappearance of the Leblanc process and its replacement by electrolytic processes, the Castner and Hargreaves processes developed in Great Britain having features embodied in most successful modern cells except those of the gravity type. The possibility of operating these processes was almost entirely dependent on power production. The original rocking mercury cell has given way to a trough type with many times the capacity of the original unit, and the use of Acheson artificial graphite for the anodes was a material improvement. The high degree of purity of the caustic soda produced by the Castner cell, fitting it for the electrolytic production of metallic sodium, was very helpful to its development. The sodium is the starting material for the manufacture of cyanide. For the last fifteen years the chlorine produced in Great Britain has been electrolytic in origin.