Treatment Of Heavy Metals Cu(Ⅱ)、Zn(Ⅱ) And Mn(Ⅱ)from Wastewater By Complexation-Ultrafiltration Technology

As a new wastewater treatment technology, menbrane separation is widely used in the treatment of industrial wastewater, drinking water and so on for its convient operation, low energy consumption and good selectivity etc. Polymer enhanced ultrafiltration is one of the novel technologies for wastewater treatment, it is of great significance for it can concentrate and separate heavy metal ions from wastewater.Polymer enhanced ultrafitration for the treatment of heavy metal containg wastewater was studied using self-made polyvinyl butyral (PVB) hollow fiber ultrafiltration membrane and complexing agen copolymer of maleic acid and acrylic acid (PMA-100). Effects of mass ratio of the polymer to metal ions (mP/mM), pH, low valent metallic salt on the retention of heavy metal ions were investigated.The results show that the membrane is subjected little fouling for the treatment of wastewater containing single Cu(II), Zn(II), Mn(II), and the rejection increases with the increase of mP/mM value at a certain pH value and increases with the increase of pH at a certain mP/mM. The retention of metal ions decreases with the addition of low valent metallic salt. The rejection of Cu(II), Zn(II), Mn(II) can be greater than99%at mP/mM6,7,6, respectively, and pH5.3,6.8,6.1respectively, for the treatment of wastewater containg single metal ion Cu(II), Zn(Ⅱ), Mn(Ⅱ).The results show that the rejections of heavy metallic ions increase with the increase of mP/mM and pH value for the treatment of wastewater containing Cu(II) and Zn(II), and Cu(II) and Mn(II). Both rejections of Cu(II) in aqueous solutions containg complex heavy metallic ions are greater than that of aqueous solution contaning single Cu(II) under the same mP/mM value, and the rejection of Zn(II) or Mn(II) is smaller than that of aqueous solution containg single Zn(II) or Mn(II). The selective separation coeffient of Cu(II) to Zn(II) for aqueous solutions containg complex heavy metallic ions is13.86at mP/mM=4, pH=5.3, and that of Cu(II) to Mn(II) is192at mP/mM3.5, pH5.3. The rejection of Cu(II) increases and the rejection of Zn(II) or Mn(II) decreases with the addition of low valent metallic salt for aqueous solutions containg complex heavy metallic ions.