Synthesis of reusable and renewable microporous organic networks for the removal of halogenated contaminants.

Microporous organic networks (MONs) have shown great potential in the removal of environmental contaminants. However, all studies have focused on the design and construction of novel and efficient adsorbents, and the recycling and reuse of adsorbates were disregarded. In this study, we report a feasible approach to synthesize renewable and reusable MONs by using target halogenated contaminants such as tetrabromobisphenol A (TBBPA), 2,3-dichlorophenol (2,3-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) as starting monomers. TBBPA, 2,3-DCP, and 2,4,6-TCP acted as hazardous contaminants and starting monomers for MONs, leading to the recycling of both adsorbents and adsorbates. The obtained TBBPA-MON, 2,3-DCP-MON, and 2,4,6-TCP-MON not only offered good reusability and large adsorption capacity for their elimination but also provided good adsorption for other phenolic contaminants relying on multiple interactions. Density functional theory calculation indicated the dominant role of π-π and hydrophobic interactions and the secondary role of hydrogen bonding interactions during the adsorption process. The used TBBPA-MON could be reused and the eluted TBBPA could be recycled and renewed for the construction of fresh MONs. This study provided a feasible approach to design and synthesize renewable MONs for environmental contaminants.