Enhancing the Performance and Recyclability of Polyaniline/TiO2 Hybrid Nanocomposite by Immobilizing with Zein/Hydroxyethyl cellulose Composites for Removal of Anionic dyes

Fabricating a stable, recyclable, and eco-friendly photocatalyst for dye treatment is vital in sustaining a clean ecosystem. In this regard, polyaniline/TiO 2 (PANI/TiO 2 ) photocatalyst was immobilized by zein/hydroxyethyl cellulose (zein/HEC) adhesive to enhance recyclability and catalytic activity. The blending of zein/HEC/PANI/TiO 2 photocatalyst involves insitu oxidative polymerization, followed by immobilization with zein/HEC functionalized composites. The PANI/TiO 2 composite was successfully grafted with the adhesive through physicochemical interaction, as evidenced by field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), and Powder X-ray diffractometer (XRD). The simultaneous thermal analysis (STA) results show that the photocatalyst has the best thermal stability relative to PANI and PANI/TiO 2 in the recommended range of dye degradation temperature. The effect of external factors like TiO 2 nanoparticle proportion, pH of the solution, and catalyst dosage was studied in response to dye degradation capacity. The synthesized catalyst is efficient to degrade methyl orange in a wide range of pH. The kinetics of the catalysis reaction obeys first order kinetics. The maximum degradation efficiency achieved was 97.9 and 84.3% in the presence and absence of light, respectively. The catalyst was easily recovered by decantation, and its catalytic efficacy was more than 94% after five cycles. Hence, it is a promising alternative for decolorizing anionic dyes from wastewater.