Desalination of Dye by Charged Mosaic Membrane

Abstract

Desalination and purification of dye can improve its quality and value. Membrane separation technology is one of the main technologies of dye desalination and purification. The charged mosaic membrane (CMM) is prepared by interfacial polymerization (IP) in this paper. And then it is applied in desalination and purification of crude dye. The results shows Rejection of the CMM for NaCl and Reactive Light Yellow (PF-6GS) is 13.2% and 99.2%, respectively. Its flux increases from 6.22 L·m-2·h-1 to 18.5 L·m-2·h-1 when the operating pressure increases from 0.2MPa to 0.5Mpa. Its flux reduces from 13.32 L·m-2·h-1 to 11.11 L· m-2·h-1 and its rejection for NaCl gradually improves from12.5% to 13.7% when NaCl concentration increases from 500 mg·L-1 to 2000mg·L-1. Its flux gradually reduces from 10.17 L·m-2·h-1 to 8.21 L·m-2·h-1 and the rejection for the dye all exceeds 99.00% when the PF-6GS concentration increases from 500mg·L-1 to 2000mg·L-1. After the crude dye is desalinated via five times the NaCl concentration in dye solution reduces from 8775mg·L-1 to 658mg·L-1, the conductivity of dye solution reduces from 28.6 ms/m to 8.92 ms/m, dye purity increases from 72.6% to 97.0%.