| 摘要 |
A process for the precipitation of aqueous plastics dispersions containing polyvinyl alcohol, preferably from waste waters, and separation of the polymeric solids content, which comprises adding the following to the dispersion in order, with thorough mixing: a) a boric acid component, b) a basic compound for making the pH alkaline, then c) an iron salt and d) a cationic polymeric polyelectrolyte, and isolating the precipitate which forms in the alkaline medium. The process according to the invention is advantageously applicable in all relevant sectors of technology and waste water treatment in which polymer dispersions containing polyvinyl alcohol are used or have to be disposed of, and where waste waters in which dispersions containing polyvinyl alcohol are present have to be processed. Degrees of clarification of more than 95% can be achieved. |
