Magnetic Fe<sub>3</sub>O<sub>4</sub> Nanoparticle/ZIF-8 Composites for Contaminant Removal from Water and Enhanced Flame Retardancy of Flexible Polyurethane Foams
Zhoumei Xu, Fukai Chu, Xiaoyu Luo, Xin Jiang, Liang Cheng, Lei Song, Yanbei Hou, Weizhao Hu
Abstract
In order to separate heavy-metal ions from contaminated wastewater and further realize the reutilization of waste adsorbent, magnetic composites with flowerlike structure were successfully synthesized. After the absorption of Cu2+ ions, hybrids can be used as effective coatings to enhance the fire safety of flexible polyurethane foam (FPUF) through a dip-coating method. As-fabricated metal–organic framework (MOF)-based composites exhibited a core–shell and flowerlike structure with high thermal stability. The maximum adsorption capacity for Cu2+ could reach 292.13 mg·g–1, calculated from the Langmuir isotherm model. In order to reutilize the adsorbed Cu2+ ions, the CuO-loaded MOF-derived Fe3O4@ZnO@CuO (MO) was obtained with a simple heat treatment. The effectivity of MO as a fire-safety coating for inhibiting the release of heat and toxic gases of FPUF was satisfactory. The application of this MOF-based composite will provide useful insights into the design of bifunctional materials for efficient wastewater remediation and fire-safety coatings.