Electrodialysis water splitting process

A process for a production of high purity alkali from salt, said process comprising the steps of:

• (a) processing a salt solution feedstream in an electrodialysis cell comprising bipolar membranes so as to produce an alkali solution containing a salt impurity;
• (b) passing the solution of step (a) through a chromatographic column containing an amphoteric ion exchange resin so as to recover a purified alkali solution and a solution containing the salt;
• and
• (c) recycling the salt solution from step (b) to join the feed stream of step (a).

A process for acidifying a brine feed in at least one chlor-alkali cell, said process comprising the steps of:

• (a) subjecting a brine stream containing alkali metal chlorate to a chromatographic separation step so as to obtain a first stream that is substantially free of the chlorate contaminant and a second stream containing chlorate;
• (b) providing a water splitter cell having bipolar membranes;
• (c) processing the first stream of step (a) in said water splitter cell to obtain an acidified brine solution;
• (d) forming a third stream by combining said second stream of step (a) with said acidified brine solution of step c, said third stream having an equivalent amount of alkali;
• (e) providing a chlor-alkali membrane electrolyzer;
• and
• (f) forwarding said third stream of step (d) to said electrolyzer of step (e).