Phosphoric acid functionalized superhydrophilic and underwater superoleophobic UiO-66/polyester fabric composite membrane for efficient oil/water separation and Gd(III) recovery

Abstract

Efficient treatment of complex rare earth (RE) smelting wastewater has drawn great attention due to its potential environmental toxicity and the high demand of RE in modern technologies. However, it is still a challenge to achieve the simultaneous recovering RE and separating oil from wastewater. This study makes the first attempt to fabricate a versatile membrane, namely H-UiO-66-PF2, by loading 2-hydroxyphosphono acetic acid functionalized UiO-66 on polyester fabric through one-pot reaction strategy, and reports for the first time the simultaneous separation of oil/water mixtures and recovery of Gd(III). The H-UiO-66-PF2 exhibits standout oil/water separation performance with water flux up to 126,300 L·m−2·h−1 and separation efficiency above 99.8 %. Besides, the maximum adsorption capacity of H-UiO-66-PF2 for Gd(III) is reached 156.5 mg/g, adsorption equilibrium time is within 60 min. Moreover, the H-UiO-66-PF2 possesses high stability and recyclability, even after 20 cycles, separation efficiency and flux are 98.9 % and 105,200 L·m−2·h−1, respectively. Most notably, in addition to the separation of oil/water emulsion, complete Gd(III) capture is achieved from wastewater through filtration process. Therefore, this work provides a new design strategy to fabricate the composite membrane with great prospects for sophisticated smelting wastewater cleanup.