Antifouling superhydrophilic porous glass membrane based on sulfobetaine prepared by thiol−ene click chemistry for high-efficiency oil/water separation

Abstract

Compared to superhydrophobic/superoleophilic membranes for high-efficiency oil/water separation, superhydrophilic membranes displaying underwater superoleophobic properties show improved antifouling performance. Nevertheless, superhydrophilic/underwater superoleophobic surfaces reported so far, in general, are susceptible to oil contamination. In addition, the tricky fabrication methods towards the superhydrophilic membranes also severely limit practical applications of such materials. Herein, we prepared novel superhydrophilic/underwater superoleophobic porous glass membranes with excellent oil fouling resistance via one-step in situ growth of silicone nanofilament network layers on the surface of sand particle-based sintered glass filters using vinyltrichlorosilane (VTCS) as a precursor, followed by grafting of a thiol-functionalized of sulfobetaine by thiol-ene click chemistry. The sulfobetaine-modified porous glass membranes showed excellent underwater superoleophobicity even for viscous crude oil. Besides, such surface-modified glass membranes exhibited high efficiency for the separation of various oil-water mixtures (>99.992%) and oil-in-water emulsions (>99.968%), even for those involved with viscous crude oil (99.982%). Owing to its superior antifouling properties, the sulfobetaine-modified glass membranes display excellent reusability for the separation of oil-water mixtures and oil-in-water emulsions. The outstanding advantages with characteristics of easy-to-fabricate, low-cost, excellent antifouling properties, and high separation performance enable the sulfobetaine-modified porous glass membranes with great potential for oily sewage treatment.