Optimizing the microstructure and properties of microfiltration carbon membranes enabled with PAN fibers for emulsified oil removal from wastewater

Separation of oil-in-water emulsion is a formidable challenge for a large variety of academia and industries involved in the fields of materials, environment, chemistry and resources. Here, microfiltration carbon membranes (MFCMs) were fabricated by the blending of polyacrylonitrile fibers (PANf) and phenolic resin as starting materials through the processes of shaping and pyrolysis. The functional groups, thermal stability, porous structure, microstructure, mechanical strength, morphology and hydrophilicity of the MFCMs were characterized by Fourier transform infrared spectrometer, thermogravimetric analyzer, bubble pressure method, X-ray diffraction, electronic universal tester, scanning electron microscope and water contact angle tester, respectively. The separation performance of MFCMs with respect to the removal of emulsified oil from wastewater was investigated by varying the PANf amount, reusability and antifouling ability. The results showed that the incorporation of PANf enhanced the thermal stability of the precursor membranes. As the PANf amount increases in precursor membranes, the average pore size and mechanical strength of MFCMs gradually decrease, together with the increment of porosity and hydrophilicity. The optimal oil rejection reaches to 94.2 %, along with the permeation flux of 15000 kg & BULL;m(-2)& BULL;h(-1)& BULL;MPa-1 for MFCMs made by PANf in a content of 3 %. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

Separating oil-in-water emulsion is a major challenge in various fields including materials, environment, chemistry and resources. In this study, microfiltration carbon membranes (MFCMs) were fabricated using polyacrylonitrile fibers (PANf) and phenolic resin. The MFCMs showed enhanced thermal stability and improved separation performance for removing oil from wastewater.