PROCESS FOR RETAINING A SUBSTANCE DISSOLVED IN A SOLUTION

摘要

The process consists firstly in adding, to the solution, an excess of a polyelectrolyte capable of forming an ionic association with the dissolved substance which it is desired to retain, and then in bringing the solution thus obtained into contact with a material possessing ionic groups which retain the polyelectrolyte by virtue of its ionic groups not associated with the said substance. The solution and the material can be brought into contact either by filtration or by tangential bathing. The polyelectrolyte can be retained either by ion exchange or by a charge repulsion effect. The material is advantageously a fibrous material of which the ionic groups are obtained by grafting.