A method for continuous regeneration of electroless nickel solutions consisting of a system of modified electrodialysis equipment and adapted electroless nickel bath compositions has been developed. Compared to presently used technologies under production environments, this technology has a higher selectivity for separation of those species responsible for the limited bath life under conventional operation of electroless nickel solutions, namely sodium, sulfate, and orthophosphite. The advantages of this technology are theoretical unlimited bath-life extension, proven under production conditions for at least 130 MTO; consistent plating rate, appearance, and quality of the deposits; higher efficiency for electroless nickel replenishment chemicals and lower solution maintenance; higher bath loading of up to 50 percent possible due to additional water transport through membranes (rinsewater recycling possible); and higher productivity from higher plating rate and less frequent production interruption (by make-up, tank cleaning, etc.) and fewer rejects resulting in reduced total production cost.
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