Study on the Treatment of Industrial Wastewater Containing Pb 2+ Ion Using a Coupling Process of Polymer Complexation-Ultrafiltration

A batch complexation-ultrafiltration coupling process was studied at the laboratory level for pollutant removal and wastewater reuse from industrial wastewater containing lead (Pb2+) ion. This process was used to concentrate and recover lead from acetate solution and to reuse the wastewater. Pb2+ ion was so small that it could not be retained by ultrafiltration membrane, which was a polyvinyl chloride (PVC) hollow fiber membrane with the molecular weight cut-off of 50,000. Therefore, Pb2+ ion was first complexed with a water-soluble macroligand (polyacrylic acid) and then it was removed. Effects of loading ratio (L), pH value, operating pressure (ΔP), volume concentration factor (VCF), and tangential linear velocity (VL ) across the membranes on the rejection (R) and permeate flux (J) were investigated. At better operating conditions (pH=7.15, L=1, ΔP=200 Kpa and V L =0.6 m·s−1), the rejection of Pb2+ ion was more than 99.98%, whereas the smallest permeate flux was 38 L/m2hr. Besides, the permeate water could be reused under better operating conditions.