Novel phosphite-based porous organic polymers for efficient removal of sulfur-containing antibiotics from water

[Display omitted] •Phosphite-based COPs were synthesized for the removal of SMX from water.•Novel PCOP-II showed superior SMX adsorption compared to benchmark materials.•PCOPs retained their adsorption performance in the presence of competing species.•PCOPs showed excellent reusability as well as good thermal stability.•Phosphite-based COP is promising for sulfur-containing PPCP adsorption. Water contamination by pharmaceutical and personal care products (PPCPs), particularly sulfur- containing PPCPs such as sulfamethoxazole (SMX), is a major environmental concern. In this study, phosphite-based porous covalent organic polymers (PCOP-I and PCOP-II) with numerous aromatic and acidic phosphite sites, large surface areas (∼1263 m2/g) and hierarchical pore structures are successfully synthesized. Compared with previously reported benchmark adsorbents, PCOPs exhibited among the largest SMX adsorption capacities (∼296.6 mg g−1) and superior SMX adsorption kinetics (10 min). The superior SMX adsorption performance of PCOPs can be explained by the π–π interactions and hydrogen bonding within hierarchical pore structures with large surface areas. The SMX adsorptive capacities of PCOPs were not greatly influenced by the presence of possible competing metal ions in water, which were retained after cyclic adsorption and regeneration. These results indicate that incorporating numerous aromatic and acidic phosphite sites into COPs with hierarchical pores and large surface areas can be used to develop adsorbents that can efficiently remove sulfur-containing PPCPs from water.