Adsorption of methyl violet and brilliant blue onto poly(vinyl alcohol) membranes grafted with N-vinyl imidazole/acrylic acid

Poly(vinyl alcohol) films were grafted with two monomers using gamma radiation, acrylic acid and N-vinyl imidazole. The ability of these membranes to adsorb the dyes, methyl violet and brilliant blue, has been investigated. The data show that untreated or alkali treated membranes adsorb methyl violet, but they did not adsorb brilliant blue. In contrast, acidic treated membranes do adsorb brilliant blue, and did not adsorb methyl violet. This indicates that these membranes could be used for the separation of both dyes. Also it was found that the dye uptake increases with the increase in the degree of grafting.