Carbon Membranes

Abstract

AbstractCarbon membranes are considered a relatively new addition to the mainstream of membrane material research. The significant number of publications in recent years shows the tremendous growth and development efforts in this research field. Carbon membranes can be fabricated by heat treatment from various types of polymeric precursor membranes such as polyimides and derivatives, polyacrylonitrile, phenolic resin, polyacrylonitrile (PAN), polyfurfuryl alcohol (PFA), polyetherimide (PEI), polyphenylene oxide (PPO), polyvinylidene chloride (PVDC), and polyphthalazinone ether sulfone ketone (PPESK). Carbon membranes can be divided into two categories, namely, supported and unsupported. The typical characterization methods used for carbon membranes can be classified into membrane performance evaluation and physical characterization. Physical characterization includes thermogravimetry analysis (TGA), X‐ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), adsorption and sorption experiments, and elemental analysis. A further explanation of each process parameter to obtain carbon membranes of highest quality is provided. In addition, the performances of various types of carbon membranes developed by previous researchers for different gas separation applications are also summarized. Furthermore, the potential applications and future directions of carbon membranes in gas separation processes are identified in this review. Other potential processes for carbon membranes including pervaporation, water treatment, and membrane reactor are also emphasized. Although significant research has been conducted since the development of carbon membranes, the need to extensively improve the gas permeation properties of these membranes still remains important if it is to become a viable membrane material for industrial applications.