Cellulose hydrogel coated fabric as superoleophobic membrane for oily wastewater treatment

Oily wastewater is a major problem, especially in developing countries. Current conventional treatments require intensive energy, large space, and potentially releasing a huge amount of methane gas. Membrane treatment is one of the most promising methods to separate liquid-liquid mixture or emulsion. Here, we report a surface wettability-based membrane to separate an oil-water mixture. The membrane made from all biodegradable materials consists of cellulose and citric acid coated in cotton fabric. Citric acid cross-linked with cellulose produces better physical attachment. Cellulose produces a hydrogel-like coating layer. The membrane shows superoleophobic properties by its high underwater oil contact angle. Our separation test shows a membrane capable to separate oil-water mixture in a continuous system. These findings are potential for organic-based membrane development for oily wastewater separation.