Preparation of fluorine-free superwetting metal-organic frameworks/polyhedral oligomeric silsesquioxanes composites for oil absorption and exceedingly high flux emulsion separation

Abstract

Background

Oil spills and emulsified water-in-oil mixtures from industrial processes pose a serious threat to organisms on earth. To address these environmental challenges, methods utilizing superwetting materials to efficiently treat emulsified oil/water mixtures have drawn noteworthy interest in the past few years.

Method

Herein, we prepared a superhydrophobic metal-organic frameworks (MOF)/polyhedral oligomeric silsesquioxanes (POSS) composite (AlTz-68-POSS). It was then used to modify melamine sponge (MS) to prepare superhydrophobic sponge, AlTz-68-POSS@MS.

Significant finding

AlTz-68-POSS@MS exhibited distinguished organic solvents absorption capacities of up to 129 g/g. Moreover, it demonstrated outstanding separation performance for surfactant-stabilized water-in-oil emulsion (SWOE), achieving exceedingly high separation fluxes of up to 8,670 L m^-2 h^-1 under gravity-driven conditions, and 1,531,000 L m^-2 h^-1 bar^-1 under external pressure-driven tests. Moreover, the oil purity in the all filtrates exceeded 99.98 wt%. In comparison with many other kinds of superwetting MOF-modified composites, the AlTz-68-POSS@MS shows excellent fluxes and superior separation efficiencies for SWOEs.