Notice of Retraction Removal of Heavy Metals from Plating Wastewater by Using Complexation-Ultrafiltration Process

Notice of Retraction After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles. We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper. The presenting author of this paper has the option to appeal this decision by contacting TPII@ieee.org. Complexation-ultraflltration process was employed to remove Ni(II), Cu(II), Zn(II) and Cr(III) from plating wastewater. Polyacrylic acid sodium (PAASS) as a water-soluble polymer was used for complexing the cationic forms of the heavy metals before filtration. The size of the complex has to be larger than the selected membranes so the complex can be retained. Permeate water is then purified from the heavy metals. Filtration experiments were performed with ultrafiltration membrane system, equipped with a polysulfone memebrane with a 10,000 Da cut-off. Different parameters, affecting the percentage rejection of the metals, such as pH, loading ratio, and permeate flux (FVC) have been investigated. The concentrated retentates were used further for the decomplexation, after the decomplexation, diafiltration experiments were carried out at pH 1.5 using dilute H2SO4 solution. All the four metals were found to be extracted from the metal-PAASS complexes with satisfaction. It was also found that the complexing performance of the PAASS regenerated did not change compared with the fresh PAASS.