Engineering Surface Wettability of Pyrolyzed Nano-Silicon Carbide/Alumina Composite Ceramic Membranes: Fabrication, Characterization, and Their Application

This study carried out the decoration of silicon carbide (SiC) nanoparticles on ceramic alumina support using a polyvinyl alcohol (PVA) and glutaraldehyde (GA) network to develop an efficient membrane for treating real-produced water (PW). This was achieved by using cycles of dip-coating of SiC-PVA/GA followed by pyrolysis, resulting in a uniform and continuous growth of the SiC/C active layer on the ceramic support. The resultant SiC-PVA/GA@Alumina membranes exhibited unique surface wettability behavior, being super-hydrophilic in air and super-oleophobic underwater. The surface functionalities and morphological analysis indicated the successful growth of the pyrolyzed SiC/C active layer on the ceramic alumina support. The effect of varying the cycles of dip-coating and pyrolysis on the membrane performance was also studied, and the membranes were labeled as P-nC-SiC-PVA/GA@Alumina. Among the various fabricated membranes, the P-2C-SiC-PVA/GA@Alumina exhibited a super-hydrophilic character with a water contact angle in air (θ_{A, W}) of ∼4° and a super-oleophobic surface with an underwater oil contact angle (θ_{O, W}) of ∼151.4°. As a result, the P-2C-SiC-PVA/GA@Alumina membrane displayed a maximum rejection of total organic carbon (TOC) reaching 83.6% with a flux of 65.8 L m⁻²h⁻¹ at 1.2 bar. In comparison, the non-pyrolyzed P-2C-PVA/GA@Alumina membrane demonstrated a flux of 150 L m⁻² h⁻¹ with a corresponding TOC rejection of 15.9%. Hence, the current study presents an efficient and simple approach to successfully decorate nanoparticles on a ceramic support, yielding an effective membrane with special surface wettability features for the sustainable treatment of real produced water (PW).