GB434488A - Process of producing hydrogen peroxide - Google Patents

Abstract

A continuous process of producing hydrogen peroxide consists in electrolyzing, by passing through an inter - electrode space without diaphragm, a flowing solution of a bisulphate whose specific gravity is raised beyond 1,2 by addition of sulphuric acid, so that no salt will be precipitated and the bisulphate only incompletely converted to persulphate, distilling the electrolyzed solution without addition of steam by feeding in a thin layer over a heating surface from which hydrogen peroxide will be distilled and instantly be free to pass from the heated layer for condensation, the persulphate being again converted to bisulphate forming a solution having the same content of bisulphate and sulphuric acid as the original solution, the condensed distillate being withdrawn and the residual solution after addition of the consumed water being recycled. Suitable electrolyzing apparatus is described in Specification 430,748. The electrolyzed solution may be allowed to flow down over the external surface of internally heated piping within the distilling apparatus. The outer walls of outer jackets of the apparatus may be heated or cooled. The cell is fed with fresh solution at the same rate as the electrolyzed solution is discharged. The efficiency is increased by reducing the space between anode and cathode, for instance by suspension therein of bodies of glass or other indifferent material. The discharged peroxide and bisulphate solution may be led to collecting vessels through valves which change over automatically to switch the feed from a full to an empty vessel. British Specification 390,549 and U.S.A. Specification 1,851,961 are referred to.