Ultrasound assisted photocatalytic degradation of isoproturon and triasulfuron herbicides using visible light driven impregnated zinc oxide catalysts

Herbicides in wastewater are considered as a serious issue to environmental pollution. Different impregnated metal zinc oxide (Cu/ZnO and Ni/ZnO) as catalysts were prepared through wet impregnation method for the degradation of herbicides Isoproturon and triasulfuron. The prepared impregnated catalysts were characterized using scanning electron microscopy (SEM) and x-ray diffraction (XRD), energy dispersive x-ray (EDX) analysis, Fourier-transform infrared spectroscopyand surface area. The degradation of selected herbicides were investigated using combined effect of photocatalysis and sonication. The experimental parameters such as pH, irradiation time, photocatalyst dose, effect of oxidants, diverse ion effect, herbicide concentration and catalyst reusability have been optimized. The percent removal of isoproturon was found to be 99 and 98% at pH 7 and triasulfuron was 98% at pH 6 using Cu/ZnO and 99% at pH 7 using Ni/ZnO photocatalysts respectively.

Automated summary

Herbicides in wastewater pose a serious threat to environmental pollution. Impregnated metal zinc oxide catalysts (Cu/ZnO and Ni/ZnO) were prepared and characterized for the degradation of herbicides Isoproturon and triasulfuron. The combined effect of photocatalysis and sonication was utilized to investigate the degradation of selected herbicides. Optimization of parameters such as pH, irradiation time, photocatalyst dose, oxidants, ion effect, herbicide concentration, and catalyst reusability was conducted. The Cu/ZnO and Ni/ZnO photocatalysts achieved removal rates of 99% and 98% for isoproturon at pH 7 and 98% for triasulfuron at pH 6, and 99% for triasulfuron at pH 7, respectively.