Effect of valences on removal of anionic pollutants using micellar-enhanced ultrafiltration

The feasibility of micellar-enhanced ultrafiltration (MEUF) for the removal of nitrate, chromate, and ferriccyanide was investigated because of ionic competition to bind on the cetylpyridinium chloride micelles. In a single pollutants system, the order of removal efficiency was nitrate <chromate <ferriccyanide: this was coincidental with the order of valences of ions. In the tertiary pollutant system, the order was the same as the single pollutant system: nitrate <chromate <ferriccyanide. The inhibition of ferriccyanide on the removal of nitrate and chromate was clearly observed, but the inhibition of chromate on the removal of nitrate was lower than that of ferriccyanide.

Removal characteristics of anionic pollutants (such as nitrate: chromate: ferriccyanide) Fig. 5. Effect of membrane MWCO on CPC concentration in the permeate in the system of equimolar nitrate/chromate/ferriccyanide. The initial concentration of nitrate, chromate, and ferriccyanide were 1 mM and the regenerated cellulose acetate membranes with molecular weight cut-off of 10000(A) and molecular weight cut-off of 3000 (B) were used for filtration at 2 bar of transmembrane pressure.