Although heavy metal contamination is an ancient problem, it remains a global concern in isolated areas. Herein, we report the design of a novel thiol-rich Zr(IV) metal-organic framework (BCM-5), assembled from meso-2,3-dimercaptosuccinic acid (Succimer), a commercially available thiol-rich metal-chelating agent used in the treatment of heavy metal poisoning. BCM-5 has been subsequently integrated into porous PVDF-HFP membranes processed via salt-leaching. The non-immobilized BCM-5 and the BCM-5@PVDF-HFP membranes were systematically evaluated for Pb(II), Cd(II), and Hg(II) capture. The results demonstrate that the metal-chelating functionalities of Succimer linker are effectively preserved within the BCM-5 framework, while immobilization of BCM-5 into PVDF-HFP membranes significantly enhances the material's dispersibility and improves its capacity for the efficient capture of the targeted heavy metals. A detailed structural, chemical, and DFT characterization of post-adsorption BCM-5 suggests that metal immobilization proceeds via chemisorption within hydrophobic, hydrophilic, and amphiphilic pore regions of BCM-5, depending on the nature of the heavy metal. Overall, this work introduces a novel approach to use metal-chelator molecules as building blocks for MOFs construction targeted to the recovery of heavy metals, while also detailing strategies for their immobilization into polymeric structures with interconnected macroporosity.
García et al. (Thu,) studied this question.