High-flux underwater superoleophobic hybrid membranes for effective oil–water separation from oil-contaminated water

Abstract

The pristine filter papers were crosslinked with polyvinyl alcohol by tolylene diisocyanate, leading to a superoleophobic surface which enables excellent oil–water separation efficiency.

A glucose modified filter paper for effective oil/water separation

“…22,23 By utilization of macromolecular layers, nano or micro-particles, nano bres, and etc., a large number of superhydrophilic and underwater superoleophobic materials have been described and drawn extensive attentions due to their highly efficient ltrations and broad application prospects on oil/water separation. 17,[24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] Filter paper, with its porous structure constructed by cotton microbers, is widely used in solid-liquid separation. Natural cotton bres consist of numerous brils of b-glucose with cuticle covered by 55% cellulose and the other non-cellulosic compounds like pectin, protein, and wax, 39 which makes primary lter paper impractical for liquid-liquid separation.…”

“…And "water-removing" ones prepared by crosslinking of hydrogels or physical depositing of hydrophilic polymers on lter papers are more favoured because of their energy efficiency, appreciable recyclability and chemical stability. 27,28,32 For example, lter paper coated with a layer of nano-brillated cellulose hydrogel displays oleophobic behavior in water and good performance in oil-in-water emulsion separation. 25 A superoleophobic lter paper prepared by a two-step dip adsorption process with paraffin wax and poly(dimethylsiloxane)-b-poly(ethylene oxide) diblock copolymer exhibits good oil-water separation efficiency for nonstabilized emulsions.…”

“…25 A superoleophobic lter paper prepared by a two-step dip adsorption process with paraffin wax and poly(dimethylsiloxane)-b-poly(ethylene oxide) diblock copolymer exhibits good oil-water separation efficiency for nonstabilized emulsions. 32 PVA-coated lter papers show high tolerance in harsh acidic, basic and alkaline environments, 28 effective oil-water mixture separation with high ux, 27 and high efficiency in separation of oil/water emulsions. 27,28 Nevertheless, most of them would be hindered in industrial applications due to the expensive reagents, intricate and time-consuming preparation process.…”

“…32 PVA-coated lter papers show high tolerance in harsh acidic, basic and alkaline environments, 28 effective oil-water mixture separation with high ux, 27 and high efficiency in separation of oil/water emulsions. 27,28 Nevertheless, most of them would be hindered in industrial applications due to the expensive reagents, intricate and time-consuming preparation process. It is still highly demanding for high-performance separators prepared with easily available substances by facile and affordable modication methods.…”

Janus Copper Mesh Film with Unidirectional Water Transportation Ability toward High Efficiency Oil/Water Separation

“…The first is the superhydrophobic/superoleophilic films that can filtrate oil from oil/water mixtures, for example, Teflon‐coated stainless steel mesh substrates, carbon‐nanotube sponges, and polydimethylsiloxiane (PDMS)‐coated nanowire membranes . The second type is films with superhydrophilicity/underwater superoleophobicity, such as hydrogel‐coated metal films, porous nitrocellulose membranes, and Cu(OH) 2 ‐coated copper mesh films, that can separate water from the mixture . Notably, all these films can only separate certain types of oil/water mixture, either light oil/water mixtures ( ρ oil < ρ water ) or heavy oil/water mixtures ( ρ oil > ρ water ).…”