GB249191A - A process for the refining of sugar juice by chlorination - Google Patents

Abstract

249,191. Ochi, S., and Kotera, F. Dec. 15, 1924. Purifying succharine liquids. - Cane, beet, or other sugar juices, or raw sugar liquor, are refined by first chlorinating at a temperature of not more than 55‹ C., removing the active chlorine by means of activated charcoal, and then neutralizing the treated juice by adding an alkaline substance. The chlorination may be effected by blowing in chlorine gas, or by passing an electric current, e.g. between platinum or graphite electrodes, through the juice which has previously been mixed with a chloride, such as radium chloride, or by the addition of a chlorine solution e.g. an aqueous solution, on one prepared by adding an acidic substance, such as chlorine or carbon dioxide, to a solution of bleaching powder &c. containing active chlorine, or by dissolving chlorine in a solution of an alkali, such as lime. The neutralization may be effected by adding an alkaline substance, such as an oxide or carbonate of an alkali or alkaline earth metal or ammonia. In one method, raw sugar, which may first be washed with water to remove molasses, is dissolved in warm water and chlorine gas is blown in with constant stirring at a temperature of 20‹ C., the solution being rapidly bleached. Activated charcoal is next added to remove the free chlorine, and the solution then neutralized with caustic soda and evaporated in a vacuum. Care is taken that the solution does not become alkaline. Filtration through charcoal may be combined with the bleaching step. The treated juice may be subjected to sulphitation and carbonation.