Cracked-earth-like titanium carbide MXene membranes with abundant hydroxyl groups for oil-in-water emulsion separation

Cracked-earth-like Ti3C2Tx MXene membranes with abundant hydroxyl groups were prepared by surface modification and facile vacuum filtration process. The as-prepared MXene membrane exhibited excellent underwater wettability and oil-in-water emulsion separation performance. [Display omitted] Membrane separation technology is one of the best methods to deal with wastewater released from oil spills and industrial wastewater. Therefore, we designed and prepared hydroxyl-rich titanium carbide MXene materials and filtered them onto a commercial polyvinylidene fluoride substrate membrane to obtain a cracked-earth-like MXene membrane with abundant hydroxyl groups and excellent underwater wettability. The underwater oil contact and sliding angles were approximately 157° and less than 3°, respectively. Moreover, the membrane effectively separated a variety of surfactant-stabilized stable emulsions with a high permeation flux of up to 6385 L m−2h−1 bar−1 and offered adequate performance after five cycles of the separation experiment. Additionally, the membrane exhibited remarkable resistance toward corrosive chemicals without any decrease in its underwater wettability performance. For example, the membrane was used to separate the emulsions containing alkali, salt, and acid. This study provides a new strategy to resolve the oily wastewater disposal problem by fabricating a cracked-earth-like MXene membrane with abundant hydroxyl groups.