Efficient adsorptive separation of Pb(Ⅱ) via Zn-triazole metal-organic framework

With the intensification of the heavy metal pollution burden, it is urgent to develop an adsorbent that can efficiently and selectively separate and capture heavy metal ions. In this work, a Zn-based triazole MOF was successfully prepared for efficient selective adsorption of Pb(II) (MOF-ZTN). The maximum uptake capacity of MOF-ZTN for Pb(II) can peak at 790 mg g −1 , with selectivity coefficients ( K s ) for Mg(II), Cd(II), Mn(II), and Co(II) being 2927, 1846, 4453, and 828, respectively, indicating that the material has a significant selective adsorption advantage for Pb(II). In the low concentration Pb(II) wastewater system, MOF-ZTN can also effectively remove more than 90 % of Pb(II) ions so that the treated wastewater quality can meet the requirements of relevant emission standards. Five consecutive adsorption-desorption cycles confirm the recyclability of MOF-ZTN. The theoretical calculation elucidates that the synergistic capture of Pb(II) by the nitrogen atoms of three triazoles in MOF-ZTN is the key to its adsorption mechanism. In short, this study shows that MOF-ZTN exhibits significant potential in the efficient capture and separation of Pb(II) and provides a new theoretical basis for the application of MOFs within the domain of environmental protection.