Effect of Zr+4 doping on characteristics and sonocatalytic activity of TiO2/carbon nanotubes composite catalyst for degradation of chlorpyrifos

Abstract

Nanotitania/carbon nanotubes composites were prepared using the sol-gel method with different nanotitania: carbon nanotubes ratios. The composite sample was modified with zirconium cation (IV). The prepared composites were characterized with different techniques using thermogravimetric analysis (TGA), nitrogen adsorption, transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), diffuse reflectance spectroscopy (DRS) and Fourier transform infrared spectroscopy (FTIR). Sonocatalytic degradation efficiency of the prepared sonocatalysts was tested for sonocatalytic degradation of chlorpyrifos at different application conditions such as the effect of chlorpyrifos concentration, temperature, catalyst dosage, ultrasonic power and the presence of radiation light. Zirconium modified nanotitania/carbon nanotubes composite (ZCT10) shows the maximum sonocatalytic activity (91.5% after 60 min) and obeyed pseudo-first order kinetic models. The optimum degradation efficiency was also confirmed at 2.0 g/L as catalyst dosage and increase with both of application temperature and ultrasonic power. The presence of radiation light can also enhance the activity of sonocatalysts. Catalyst reusability experiments showed that catalysts are well reusable for degradation of chlorpyrifos by the sonocatalytic process.