Development of β-cyclodextrin-modified poly(chloromethyl styrene) resin for efficient adsorption of Cu(Ⅱ) and tetracycline

The host–guest β-cyclodextrin has attracted much attention for potential application in various fields due to its low price, natural pores, and functionality. Herein, we report a method using 1,4-phenylene diisocyanate (PPDI) to fabricate β-cyclodextrin (CD)-modified poly(chloromethyl styrene) (PCMS) resin, namely, PCMS@PPDI-CD. β-Cyclodextrin was utilized to improve the adsorption performance of PCMS, which was then applied to anchor β-cyclodextrin powder. The product exhibits excellent renewability and availability due to the application of PCMS. The adsorption performance was fully exerted by the combination of β-cyclodextrin and PCMS. SEM mapping, FTIR, TG, BET, and XPS analyses were conducted to explore the morphological and structural properties of PCMS@PPDI-CD. Adsorption experiments show that PCMS@PPDI-CD removed 100 % of TC and 75 % of Cu(Ⅱ), and the maximum adsorption capacity for Cu(Ⅱ) and TC reached 187.6 and 266.4 mg g−1, respectively. After recycling six times, the adsorption ability of Cu(Ⅱ) and TC still achieved excellent removal performance. In addition, the chelation of the lone N pair, the hydrophobicity of the cavity, H-bonding, complexation, n-π interaction, and porous structure showed the possible mechanism. We used computational formulas to simulate the adsorption state and found that the resin is theoretically feasible. Most importantly, we propose a novel application of PCMS@PPDI-CD. This work shows that the resulting PCMS@PPDI-CD is highly efficient and can be easily recycled, making it an attractive resin for adsorption.