Study of Photocatalytic Activity of Zinc Oxide Nanoparticles Extracted from Leaching Residue of Zinc Melting Factory to Remove NB21 dye in UV light

Textile and dyeing industries are important industries in every country. Reactive colors soluble in water due to high brightness, low energy consumption and simple application method are one of the most important groups of colors used in the textile industries. Wastewater containing colors such as R198 is hazardous to the ecosystem and health, so a way to remove color from the wastewater is needed. The photocatalytic process is one of the advanced oxidation processes, that has shown the capability for eliminating various toxic and degradable compounds. In this study, zinc oxide nanoparticles were obtained from the purified solution of the residue of Zinc melting factory in Bafgh. The nanoparticles obtained by various devices were studied and analyzed. The formation, purity and optical properties of Zinc Oxide nanoparticles were investigated by Fourier Transform Infrared Spectrometer (FTIR) test. Finally, in order to investigate the photocatalytic properties of the nanostructures, NB21 reactive color, which is one of the most applicable and important colors in the textile industry, and is harmful to the environment was removed. The three parameters of color concentration, pH and amount of nanoparticle on its dye under UV rays were studied. The results of X-Ray Diffraction pattern (XRD), represents the crystalline and hexagonal structure of the samples. According to the Transmitted Electron Microscope (TEM) images, the sample has clear spherical shapes and distinct hexagonal dimensions in the range of 40-120 nm. Under optimum conditions, with 15 ml of color solution with concentration 0.1912 g/L, pH=5 and nanoparticle 0.06 gram at time interval of 120 minutes with application of bleaching process under UV rays, 94% of the color was degraded.