Synthesis of Polymeric Sunscreen Photocatalyst ZnO2, CuO2, PbO2, and CdO2 Using Ethylene Glycol for Reactive Blue Dye Removal from Textile Waste Water

Abstract

Industrial dyes are the main cause of environmental pollution. The present study consists of the removal of synthetic anionic dye using batch study with photocatalyst using adsorption technology. The adsorbents were prepared using the chemical synthesis method. At pH 5, ZnO₂ shows maximum results in the Reactive Blue dye. At the same time, CuO₂ shows maximum results at pH 2. In contrast, the CdO₂ and PbO₂ nanoparticles presented maximum results at pH 4. The optimum dose for all four kinds of nanoparticles, ZnO₂, CuO₂, PbO₂, and CdO₂, was found to be 0.5 g/50 mL for the elimination of anionic dye at pH 2, 4, and 5. For ZnO₂, CuO₂, PbO₂, and CdO₂ nano photocatalyst, the maximum percentage of dye removal was recorded at 0.05 catalyst dosage. The starting concentration of dye in the series of 25–200 mg/L was measured as optimum for the highest deletion of anionic stain by dissimilar kinds of chosen adsorbents. The maximum adsorption capacity of ZnO₂ (85.69 mg/L), CuO₂ (79.04 mg/L), PbO₂ (64.12 mg/L), and CdO₂ (51.58 mg/L) was obtained at 100, 150 and 75 mg/L dye concentration. The optimum temperature for the highest removal of anionic dyes was detected at 37 °C, and the reduction examined a decline in the adsorption capacity of whole compounds as temperature decreases. It represented the exothermic behavior of all sorption processes intricate in the exclusion of certain anionic dyes. Langmuir biosorption isotherms were given the best fitness on equilibrium biosorption data, whereas the pseudo 2nd order displayed the fitness on adsorption kinetic data. Additionally, data show that the elimination of Reactive Blue dye by adsorption with ZnO₂, CuO₂, PbO₂, and CdO₂ nanoparticles follows second-order kinetics (R² = 0.9855) and Langmuir model (0.9997). Utmost desorption was attained by 0.5 N sodium hydroxide. Fourier Transform Infrared (FTIR) was used to characterize the nanoparticles, which gave information about the functional groups on dyes. So, by using the adsorption technology, maximum dye removal from wastewater was observed, and ZnO₂ showed maximum percentage removal of anionic dye. Reactive Blue is effectively degraded in aqueous solution by photocatalysis with ZnO₂ assistance while being exposed to ultraviolet (UV) radiation.

Graphical Abstract