The application of ultrafiltration composite GO/PAN membranes for removing dyes from textile wastewater

摘要

Wastewater produced by the textile industry is a large percentage of total wastewater subjected to treatment processes. This paper presents the results of research on the use of ultrafiltration composite graphene oxide (GO)/polyacrylonitrile (PAN) membranes (containing 0.8% (membrane A), 4.0% (membrane B), 7.7% w/w (membrane C) of GO in PAN matrix) for removal of dyes from synthetic sewage and real laundry wastewater. Cationic dyes (Indigo synthetic - IS; Methylene blue - MB) and anionic dyes (Thymol blue -TB; Congo red - CR) were selected for the study. During testing of the flow of synthetic sewage through membranes, it was shown that TB and CR did not impair the transport properties of GO/PAN membranes, which for subsequent GO/PAN membranes were: similar to 24, congruent to 35, and similar to 58 L/m(2) h bar, respectively. On the other hand, decrease of permeate flux was noted for synthetic sewage containing the IS and MB cationic dyes. The investigation of actual laundry wastewater showed a reduction in volumetric permeate flux by: 35% (membrane A), 61% (membrane B), and 50% (membrane C). The GO/PAN composite membranes could be used to remove anionic dyes, because they effectively (in nearly 100%) removed TB and CR, while cationic dyes (IS and MB) were separated in 60% o 95%.