Design of magnetic multivariate metal–organic framework for high-efficient adsorption and rapid magnetic separation of bisphenol pollutants

Herein, a magnetic multivariate metal–organic framework (MTV-MOF) named as 95.7 %BTB/MOF-525@Fe3O4 was synthesized by one-pot mixing ligand strategy. The magnetic MTV-MOF exhibited large specific surface area (320 m2·g−1) and high porosity. The 95.7 %BTB/MOF-525@Fe3O4 was used as sorbent for extraction and enrichment of bisphenol pollutants (BPs). The experimental results demonstrated that adsorption kinetics and isotherms conform to pseudo-second-order model and Langmuir model. The maximum adsorption capacities for bisphenol F, bisphenol A, bisphenol B, bisphenol AF were 275.1, 233.6, 302.1 and 277.2 mg·g−1, respectively. With 95.7 %BTB/MOF-525@Fe3O4 as sorbent, the magnetic solid phase extraction coupling HPLC was used to detect trace BPs in environmental water. The limits of detection were determined as between 0.067 and 0.167 ng·mL−1. The enrichment factors were in the range of 242–295. The recoveries were ranged from 79.4 to 103 % with relative standard deviations not higher than 8.85 %. In addition, the recovery rate of sorbent remained above 80 % after 21 times of reuse. The work provides an effective material for extraction and removal of BPs in the environment.