Fabrication of novel ZIF‐67 Composite Microspheres for Effective Adsorption and Solid‐phase Extraction of Dyes from Water

Abstract

Abstract ZIFs type metal‐organic frameworks have been found to rapidly remove organic contaminants from water by adsorption. But ZIFs crystals are not suitable to be directly used as stationary phases of solid‐phase extraction (SPE) process, because of the non‐spherical morphology. This study reports a novel composite adsorbent, ZIF‐67 composite microspheres (ZIF‐67 CMs), synthesized via in‐situ growing ZIF‐67 nanoparticles (ZIF‐67 NPs) on the outer surface of resin microspheres (RMs). The as‐synthesized ZIF‐67 CMs were characterized by SEM, XRD, FTIR, BET and TGA experiments, and the removal performance of the ZIF‐67 CMs to anion dyes were investigated. It was found that the ZIF‐67 CMs showing microsphere morphology were successfully assembled by growing ZIF‐67 NPs on RMs and exhibited favorable performance to rapidly adsorptive remove two kinds of anion dyes (Brilliant Blue G and Congo red) from water. The removal rates of the ZIF‐67 CMs to a 100 mg L −1 dye solution reached 95.9% and 99.1% in a 1 h and 5 h static adsorption, respectively. The ZIF‐67 CMs showing rapid adsorption performance were further studied as stationary phases in SPE procedures for decolorizing dye solutions. The ZIF‐67 CMs can efficiently remove more than 99% of dyes at a flow rate of 1.0 mL min −1 in a 5 min operation. The excellent SPE performance of ZIF‐67 CMs indicates the potential applications for efficiently concentrating or purifying liquid mixtures by using ZIF‐67 CMs or other ZIFs composite microspheres.