GB735081A - Process for the removal by adsorption of organic substances from liquids - Google Patents

Abstract

Artificial resins containing polar groups of moderate to strong basic character, i.e. capable of binding anions of carboxylic or glutamic acid, are employed for adsorbing colouring matter, odoriferous- and taste-substances from liquids, especially saccharine liquids. Examples of the prepartion of suitable resins involve (A) reaction, under heating, of aniline, tetraethylene pentamine, water and epichlorhydrin, drying the gel so formed, and granulating the dried gel; (B) reaction, under heating, of water, tetra-ethylene pentamine and epichlorhydrin, drying the gel so formed, and granulating the dried gel; (C) reaction, under cooling and in a concentrated sulphuric acid solution, of formaldehyde and trianisyl sulphonium chloride made from thionyl chloride and anisole in the presence of aluminium chloride, heating to produce a gel, allowing the gel to harden, granulating to the desired size, and washing with alkaline solution and then with water. Specifications 650,706 and 733,376, [Group VI], are referred to.ALSO:In the removal by adsorption of colouring matter, odoriferous and taste-substances and the like from liquids, e.g. sucrose-containing solutions, there is used an insoluble, surface-active artificial resin having polar groups of a moderate to strong basic character, i.e. capable of binding anions of carboxylic or glutamic acid. The alkalinity of the adsorbing resin is, if necessary, reduced before use to pH below 9 by treatment with an electrolyte solution, e.g. a solution of an acid such as hydrochloric acid, a bicarbonate, ammonium sulphate or ammonium chloride. The resin is preferably employed in a swollen condition, e.g. having dry substance less than 400 g./litre, and the temperature is preferably above 70 DEG C. The liquid may be purified preliminarily with the aid of calcium carbonate, calcium phosphate, aluminium hydroxide, diatomaceous earth, blood, activated carbon, bone black, washed, sulphuric-acid treated sawdust, or a cation exchanger such as that prepared by treating coal with sulphuric acid. The process is of particular advantage in treating liquids containing invert sugar and glucose. The resin is regenerated by washing with an alkaline solution. Examples are concerned with decolourizing the liquid obtained on washing the syrup film from centrifuged Cuba raw sugar and the liquid centrifuged from a white beet sugar boiling, the liquid being percolated over granules of a dried resin gel prepared by the reaction of aniline, tetraethylene pentamine, water and epichlorhydrin. Specifications 650,706 and 733,376 are referred to.