ES450008A1 - A method of production of an alkaline metal carbonate. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

A method of producing an alkali metal carbonate in an electrolytic cell, consisting of: A. electrolyzing an alkali metal chloride into an electrolytic cell with an anode and a cathode in anolyte and catholyte compartments, separated by a thermoselective cation exchange membrane that is impermeable to hydraulic flow and is separated from the cathode; B. inject carbon dioxide into the catholyte compartment to convert virtually all of the alkali metal hydroxide that forms there into alkali metal carbonate; C. use a current density greater than 1 amp/inch2 (15.5 A/dm2), of sufficient magnitude to reduce the alkali metal chloride in the catholytic solid to less than 400 parts per million; D. separating the alkali metal carbonate from the catholyte compartment; E. where the membrane has the following characteristics: 1. It consists essentially of a film of a copolymer with repeated periodic units of the formula: **(See formula)** and -CXX'-CE2- (II) where R represents the group **(See formula)** where R'is fluorine or perfluoroalkyl of 1 to 10 carbon atoms, Y is fluorine or trifluoromethyl and m is 1, 2 or 3; n is 0 or 1; A is H, Na, or K; X is fluorine, chlorine, or trifluoromethyl; and X1 is X or CF3- (CF2) z-, where z is 0 or an integer from 1 to 5; the units of formula (I) being in sufficient proportion to form a copolymer that in the acid form has an equivalent weight of -S03H of around 1000 to 1400 and 2. is capable, when immersed in water at 100ºC, of absorbing at least 15% by weight of water. (Machine-translation by Google Translate, not legally binding)