School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China.
School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China.
Chemosphere. 2019 Dec;236:124330. doi: 10.1016/j.chemosphere.2019.07.061. Epub 2019 Jul 10.
Shear-induced dissociation coupling with ultrafiltration (SID-UF) is an efficient and environment-friendly technology for the separation of heavy metal ions. In this paper, SID-UF was successfully employed for the selective recovery of nickel, zinc and copper from electroplating effluent using poly (acrylic acid) sodium (PAAS) and copolymer of maleic acid and acrylic acid (PMA) as complexants, respectively. The effects of the pH, mass ratio of polymer to metal ions (P/M) and the rotating speed on the metals removal efficiency are discussed in detail. The shear stabilities of the polymer-metal complexes were explored and the complexes critical shear rates (γ) were calculated. The results show that the order of the shear stabilities of PAA-metal complex is PAA-Zn > PAA-Cu > PAA-Ni, and that of PMA-metal complex is PMA-Cu > PMA-Ni > PMA-Zn. In addition, the construction of the stable structures of complexes and the calculation of the energies of the frontier molecular orbital by density functional theory method further predict and confirm the shear stabilities of the polymer-metal complexes.
剪切诱导解离与超滤(SID-UF)结合是一种高效、环保的分离重金属离子的技术。本文采用聚(丙烯酸)钠(PAAS)和马来酸-丙烯酸共聚物(PMA)分别作为络合剂,通过 SID-UF 成功地从电镀废水中选择性回收镍、锌和铜。详细讨论了 pH 值、聚合物与金属离子的质量比(P/M)和转速对金属去除效率的影响。探讨了聚合物-金属络合物的剪切稳定性,并计算了络合物的临界剪切速率(γ)。结果表明,PAA-金属络合物的剪切稳定性顺序为 PAA-Zn>PAA-Cu>PAA-Ni,而 PMA-金属络合物的剪切稳定性顺序为 PMA-Cu>PMA-Ni>PMA-Zn。此外,通过密度泛函理论方法计算前线分子轨道能量,进一步预测和证实了聚合物-金属络合物的稳定性。