STUDY ON PREPARATION AND PERFORMANCE OF NANO-ZINC OXIDE

In this paper, zinc oxide nanocrystals were prepared by homogeneous precipitation method using urea and zinc nitrate as raw materials. Wet peroxide oxidation (WPO) and catalytic wet oxidation (CWO) of oily wastewater were investigated. More than 80% chemical oxygen demand (COD) removal from oily wastewater was achieved using nano-zinc oxide catalytic wet oxidation (CWO) under the following conditions using a 0.6 L batch reactor: temperature is 340°C and concentration of nano-zinc oxide is 100 mg/L. 99.7% of COD removal was achieved using WPO under the following conditions: temperature is 320°C, residence time is 20 min, H2O2 dose is 200 mg/L and initial COD is 10000 mg/L.