Process for separating polyvinyl alcohol from its solution

Abstract From the Canadian patent

A process for the separation or extraction of polyvinyl alcohol from its solution which includes adding to an aqueous solution comprising polyvinyl alcohol, a coating agent consisting essentially of a salt of boric acid and a salting agent which is member selected from the group consisting of inorganic acid salt of a metal of first or second groups of the periodic table, an inorganic ammonium salt and an inorganic aluminium salt; agitating the resulting mixture to coagulate the polyvinyl alcohol and separating the coagulated polyvinyl alcohol from the mixture in order to minimize the discharge of PVA in waste waters, into the environment.