At present, the functionalized Zr-based coordination polymer for heavy metal ions removal are primarily implemented via post-synthesis, and it is still a challenge to reduce the concentration of heavy metal ions to wastewater discharge standard. In this work, the 2,2′-dithiodipropionic acid modified Zr-based coordination polymer (named as Zr-DTDPA) was prepared by direct synthesis. It presented extraordinary adsorption ability in the process of removing Hg(II)/Pb(II). The optimum pH for Hg(II) and Pb(II) absorption was 4.0 and 6.0, respectively, and the saturated adsorption capacity reached 960 mg/g and 478 mg/g. The adsorption process can be exceedingly fitted by Langmuir isotherm model and pseudo-second-order (PSO) kinetic model, which indicated that chemisorption played a dominant role. Additionally, the maximum selectivity coefficient reached 21.36 × 10⁵ and 5605 for Hg(II) and Pb(II). Impressively, the residual contents of Hg(II) and Pb(II) were only 1.04 μg/L and 0.34 mg/L, which respectively reached the concentration standard of Hg(II) and Pb(II) in wastewater. Zr-DTDPA was easy to be regenerated, and the removal rate of Hg(II) had only decreased by 17.15% after ten consecutive cycles. The results of Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) suggested that the adsorption performance of Zr-DTDPA toward Hg(II)/Pb(II) was primarily determined by thiol/thio groups, and the adsorption mechanism was the interaction between sulfur atoms and Hg(II)/Pb(II) ions.

目前，用于去除重金属离子的功能化Zr基配位聚合物主要是通过后合成实现的，降低重金属离子的浓度以达到废水排放标准仍然是一个挑战。在这项工作中，通过直接合成制备了2,2'-二硫代二丙酸改性的Zr基配位聚合物（称为Zr-DTDPA）。在去除Hg（II）/ Pb（II）的过程中表现出非凡的吸附能力。Hg（II）和Pb（II）吸收的最佳pH分别为4.0和6.0，饱和吸附容量达到960 mg / g和478 mg / g。Langmuir等温模型和伪二级动力学模型可以很好地拟合吸附过程，这表明化学吸附起着主导作用。另外，对于Hg（II）和Pb（II），请参见图⁵和5605。令人印象深刻的是，Hg（II）和Pb（II）的残留量仅为1.04μg/ L和0.34 mg / L，分别达到废水中Hg（II）和Pb（II）的浓度标准。Zr-DTDPA易于再生，连续10个循环后Hg（II）的去除率仅降低了17.15％。傅立叶变换红外光谱（FT-IR）和X射线光电子能谱（XPS）的结果表明，Zr-DTDPA对Hg（II）/ Pb（II）的吸附性能主要由硫醇/硫基决定，并且吸附机理是硫原子与Hg（II）/ Pb（II）离子之间的相互作用。