Method for separating and recovering an acid
AssigneeAsahi Glass Company, Limited
InventorsYoshio Sugaya, Misaki Kanazawa, Haruhisa Miyake
Life of this patent
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Abstract
A method for separating and recovering an acid, which comprises contacting to one side of a diffusion dialysis membrane an acid solution containing an acid having an acid radical with a formula weight of at most 200 and impurities and to the other side of the membrane water or a dilute acid solution, to separate and recover the acid in the solution, wherein the diffusion dialysis membrane comprises a cation exchange membrane having certain specific properties or comprises a main layer of an anion exchanger and a surface layer of the cation exchange membrane having certain specific properties formed on the main layer at the side of which is contact with the acid solution.
Claims9
A method for separating and recovering an acid, which comprises contacting to one side of a diffusion dialysis membrane an acid solution containing an acid having an acid radical with a formula weight of at most 200 and impurities and to the other side of the membrane water or a dilute acid solution, to separate and recover the acid in the solution, wherein a cation exchange membrane containing sulfonic acid groups in an amount of from 0.5 to 4.5 meq/g dry resin and having an electrical resistance of at most 0.5 .OMEGA./cm.sup.2 as measured in the acid solution containing the acid to be recovered at a concentration of 0.5 mol/l, is used as the diffusion dialysis membrane and
- wherein the impurities are anions and acid radicals of an acid of a metal of Group 1B, 2B, 3, 4A, 4B, 5A, 6, 7A or 8 or the Periodic Table or metallic complex anions thereof.
A method for separating and recovering an acid, which comprises contacting to one side of a diffusion dialysis membrane an acid solution containing an acid having an acid radical with a formula weight of at most 200 and impurities and to the other side of the membrane water or a dilute acid solution, to selectively permeate the acid from the acid solution, wherein the diffusion dialysis membrane comprises a main layer of an anion exchanger and a layer of a cation exchanger formed on the main layer at the side which is in contact with the acid solution and wherein the impurities are anions and acid radicals of an acid of a metal of Group 1B, 2B, 3, 4A, 4B, 5A, 6, 7A, or 8 of the Periodic Table or metallic complex anions thereof.
Dependencies are inferred from the claim text.