Renewable Superhydrophobic Pvb/Sio2 Composite Membranes with Self-Repairing for High-Efficiency Emulsion Separation

Abstract

Design and constructing high performance filtration membranes for oil purification from emulsified oil/water mixtures with good durability and self-repairability is highly desired for the remediation of oily wastewater and oil recycling caused by oil leakage and oil spill, but remain a tough challenge. Herein, a facile method for the fabrication of dodecyltrichlorosilane grafted polyvinyl butyral/silica sol/silica nanoparticles (PSSD) nanofibrous membranes is developed. The as-prepared PSSD nanofibrous membranes exhibited intriguing wetting behaviors, such as superhydrophobicity in air and under oil, small sliding angle, and extremely low adhesion force. The superwettability, hierarchical porous structure, and good mechanical properties endowed the membranes with fascinating emulsion separation performance from highly emulsified oil/water mixtures, involving high separation efficiency >99.6%, large oil permeation flux of ~2316.2 L m -2 h -1 , and excellent long-term cyclic performance in 10 cycles. Additionally, PSSD nanofibrous membranes exhibited superior self-repairing performance against abrasion damages and maintained wettability and emulsion separation performance after 10 abrasion-repairing cyclic processes. The successful fabrication of such PSSD nanofibrous membranes provides a versatile strategy for developing materials with high purification performance, good repairability, and excellent durability for the oily wastewater remediation, oil spill clean-up, and oil purification.

Keywords: self-repairing, superwettability, PSSD nanofibrous membranes, Emulsion separation