Aerosol-assisted plasma processing for oil/water separation

For a long time, oily wastewater from domestic usage, petrochemical industries, and frequent oil spill accidents has posed a great threat to the environment and caused a series of environmental-related socio-economic problems. Efficient separation of oil/water mixtures has thus attracted more and more attention from both academia and industry. The membrane-based technique has recently been regarded as a promising avenue for oily wastewater remediation. However, the conventional wet-chemistry based membrane fabrication methods generally are expensive and involve a huge amount of toxic solvents, which may cause secondary pollution to the environment. Moreover, the fabrication efficiency and the required harsh reaction conditions for these conventional methods also significantly limit their further acceptance in the environmental application field. In contrast, eco-friendly plasma processing can be an alternative and promising surface modification approach for the fabrication of functional oil/water separation membranes. In this study, an aerosol-assisted plasma deposition method was proposed to functionalize polymer membranes with the aim to separate oil/water mixtures. 2-hydroxyethyl methacrylate was used as the polymerization monomer and injected into a plasma region in an aerosol form. The plasma was operated at very mild atmospheric pressure open-air conditions, and the fabrication process was very fast, in minutes level. As a result, a superhydrophilic and underwater superoleophobic thin film was successfully coated on an original hydrophobic polyester membrane surface. The surface morphology and surface chemistry of the plasma coating were investigated by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, atomic force microscopy, and scanning electron microscope. Moreover, the plasma functionalized membranes showed a superb separation efficiency towards various oil/water mixtures. This study thus contributes to a novel environmentally friendly method for surface engineering of oil/water separation membranes.

Jaar van publicatie:2022