Construction of a Mercapto-Functionalized Zr-MOF/Melamine Sponge Composite for the Efficient Removal of Oils and Heavy Metal Ions from Water
Mingbo Shi, Daiwu Lin, Renliang Huang, Wei Qi, Rongxin Su, Zhimin He
Abstract
The treatment of multicontaminant wastewater has attracted extensive attention in recent years. Herein, we synthesized a porous and hydrophobic composite (Zr-MOF-SH/MF) via the in situ growth of mercapto-functionalized Zr-metal–organic frameworks (MOFs) (Zr-MOF-SH) on the surface of a melamine formaldehyde (MF) sponge. The successful growth of hydrophobic Zr-MOF-SH, as confirmed by SEM, XRD, and XPS analysis, made the MF sponge become hydrophobic with a water contact angle of 125°. The adsorption capacity of the Zr-MOF-SH/MF composite for dichloromethane can reach up to 113 g/g. Moreover, the composite can efficiently and selectively remove Hg2+ ions from water. Especially, PCN-224-MAA/MF had an adsorption capacity of 412.5 mg/g for Hg2+ ions. The removal efficiency of Hg2+ ions increased as the oil content in the oil–water mixture increased. In addition, PCN-224-MAA/MF can be recovered and reused five times with only a slight decrease in adsorption capacity. This study provides a promising strategy for the synthesis of a dual-functional composite that exhibits excellent performance in removing oil and heavy metal ions simultaneously from water.