Highly efficient removal of emulsified oil from oily wastewater by microfiltration carbon membranes made from phenolic resin/coal.

Oily wastewater treatment is a major problem for a large variety of industrial sectors. Membrane filtration is quite promising for oil-in-water emulsion treatment by virtue of numerous eminent advantages. Here, microfiltration carbon membranes (MCMs) were prepared by the blends of phenolic resin/coal as precursor materials for efficient removal of emulsified oil from oily wastewater. The functional groups, porous structure, microstructure, morphology and hydrophilicity of the MCMs were analyzed by Fourier transform infrared spectroscopy, bubble-pressure method, X-ray diffraction, scanning electron microscope and water contact angle, respectively. The effect of coal amount in precursor materials on the structure and properties of MCMs was mainly investigated. Under operation at 0.02 MPa for trans-membrane pressure and 6mL·min for feed flowrate, the optimal oil rejection and water permeation flux is correspondingly attained to 99.1% and 21388.5kg·mhMPa for MCMs made by the precursor containing 25% coal. Besides, the antifouling ability of the as-prepared MCMs is greatly improved in comparison with the one merely made by phenolic resin. In summary, the result indicates that the as-prepared MCMs are very promising for oily wastewater treatment.