Adsorption of 4,4′-(Propane-2,2-diyl)diphenol from Aqueous Solution by a Covalent Triazine-Based Framework

4,4′-(Propane-2,2-diyl)diphenol (4,4′-PDOL) as a common endocrine-disrupting is widely used in production and life. In this study, a covalent triazine-based framework (CTF) was synthesized, and its adsorption performance for 4,4′-PDOL from aqueous solution was evaluated by batch adsorption experiments. Characterization results demonstrated that CTF had an ordered microporous structure, the Brunauer–Emmett–Teller (BET) surface area is 782.4 m 2 ·g –1, and the pore volume is 0.40 cm 3 ·g –1 . The batch adsorption experiment indicated that 4,4′-PDOL adsorption kinetics on CTF followed by pseudo-second-order kinetics and the adsorption isotherm could be well-described by the Freundlich adsorption model. 4,4′-PDOL exhibited a strong adsorption affinity because of several specific nonhydrophobic mechanisms, including hydrogen bonding, electrostatic attraction, and the micropore-filling effect. The hypothesized mechanisms were further supported by the observed pH dependence adsorption. Nearly no influence was observed by solution ionic strength and dissolved humic acids. Findings in this study highlight the potential of using CTF as an effective adsorbent for 4,4′-PDOL removal.