The removal of chromium (VI)
from aqueous solutions by Donnan dialysis has been investigated in this paper.
In this process, two anion-exchange membranes (AEMs) were used: Selemion? AMV and Neosepta? AFN. The amount of chromium (VI) removed was
determined in terms of the following parameters: initial concentration of
chromium (VI), type of anion-exchange membrane, concentration of counter-ion
and magnetic stirring rate. A 24 full factorial design analysis was performed
to screen the parameters affecting the Cr (VI) removal efficiency. Using the
experimental results, a linear mathematical model representing the influence of the
different parameters as well as their interactions was
obtained. Analysis of the variance (ANOVA), the F-test and the student’s test
shows that the type of anion-exchange membrane is the most significant parameter
affecting the chromium (VI) removal. The statistical analysis of the experimental
data assumes it to be a normal distribution.