Application of Novel C-TiO₂-CFA/PAN Photocatalytic Membranes in the Removal of Textile Dyes in Wastewater

• Main Authors: Amkelwa Mpelane, David M. Katwire, Henry H. Mungondori, Pardon Nyamukamba, Raymond T. Taziwa
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Catalysts
• Subjects: carbon-doped titanium dioxide; coal fly ash; photocatalysis; poly(acrylonitrile); methyl orange; golden yellow
• Online Access: https://www.mdpi.com/2073-4344/10/8/909

The existence of dye effluent in environmental water bodies is becoming a growing concern to environmentalists and civilians due to negative health effects. In this study, a novel poly(acrylonitrile)-membrane-supported carbon-doped titanium dioxide–coal fly ash nanocomposite (C-TiO₂-CFA/PAN) was prepared and evaluated in the removal of textiles dyes (methyl orange and golden yellow) in water. The C-TiO₂-CFA nanocomposite was prepared via sol-gel synthesis and immobilized on PAN membrane prepared via phase inversion technique. The photocatalyst was characterized by FTIR, XRD, BET surface area analysis, SEM, EDX, and DRS. FTIR analysis confirmed the existence of the expected functional groups, and XRD revealed that the C-TiO₂ was predominantly in the anatase phase, which exhibited the highest photocatalytic activity. The optimum C-TiO₂-CFA photocatalyst load on the PAN membrane was 2% w/w, and it achieved degradation efficiencies of 99.86% and 99.20% for MO and GY dyes, respectively, at pH 3.5, using a dye concentration of 10 ppm, under sunlight irradiation, in 300 min. The novel 2% C-TiO₂-CFA/PAN photocatalytic membrane proved to be very effective in the removal of textile dyes’ water. Three reusability cycles were carried out, and no significant changes were observed in the photocatalytic efficiencies. Immobilization on PAN membrane allowed easy recovery and reuse of the photocatalyst.