The assembly of polysaccharide ZIF-8-based foam for efficient adsorptive removal of PEDCs from environmental water

Abstract

ZIF-8 is a type of porous coordination metal-organic frameworks (MOFs) material with excellent adsorption properties. However, the inevitable acid-base sensitivity and low plasticity of ZIF-8 impede its application to the field of compound adsorption and separation. Here, a novel reusable monolithic MOFs foam material, polysaccharides (CMC & chitin) gels zeolitic imidazolate frameworks (PC-ZIF-8), has been developed to effectively adsorb five Phenolic Endocrine Disrupting Chemicals (PEDCs) from environmental water. In this study, the forming strategy of a continuous phase change sol-gel MOFs material was designed. The carboxymethyl cellulose and chitin hydrosol were used as the self-assembly medium for in-situ synthesizing sol-type MOFs by a one-step method. Several favorable characteristics of PC-ZIF-8 have been confirmed, including large surface area (619.47 m2/g), low density (<0.085 g/cm3), high ZIF-8 loading rate (>80%, wt%), high structural strength, high acid, and alkali tolerance, and easy recyclability. The adsorption efficiency of PC-ZIF-8 for 5 BPs in water is 92.97%− 99.12%, and the maximum adsorption capacity is 120.1–172.9 mg/g. After simple regeneration treatment, PC-ZIF-8 has been recycled 5 times, and the overall recovery rate still remains above 80.0%. The results of this study indicate that PC-ZIF-8 is a reliable adsorbent for BPs in environmental water purification.