High adsorption ZIF-67/PP hybrid membrane for rapid extraction of U(VI) from water

In this paper, ZIF-67/PP hybrid membrane (ZIF-67-N) is prepared by in situ synthesizing ZIF-67 on polymer membranes for rapid extraction of U (VI) from water. The effects of pH, contact time, and concentration of U (VI) on the adsorption of ZIF-67-N are investigated. The adsorption isotherm and kinetics analysis show an extremely high adsorption capacity of 1334.8 mg/g of ZIF-67-N which is 5.36 times higher than that of ZIF-67, and a rapid adsorption equlibrium of 20 min that is 12 times faster than ZIF-67. The adsorption process is consistent with the Freundlich isotherm equation and pseudo-second-order rate equation. ZIF-67-N also exhibits good selectivity for U (VI) in simulated seawater. The high adsorption performance of ZIF-67-N is attributed to the membrane structure that improves the utilization of coordination sites including Co-OH, C-N, and CN. To our knowledge, ZIF-67-N achieves the highest adsorption capacity among reported MOFs materials. This work provides a kind of efficient adsorption materials for rapid U (VI) extraction, which will be conducive to promoting the development of U (VI) extraction technology.