1.School of Materials Engineering, Nanjing Institute of Technology, Nanjing 211167, China ?2.Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology, Nanjing 211167, China ?3.Zhongtian Alloy Technology Co., Ltd., Nantong 226010, China
The copper nanoparticles were prepared in ultrasonic field by using the copperammonia waste water as the starting material and hydrazine hydrate as reducing agent, as well as polyvinyl pyrrolidone as surfactant. In this paper, the influence of temperature, pH value and the amount of surfactant on particle size and morphology of copper nanoparticles were studied. The optimum reaction condition was the temperature about 72 ℃, pH among 9.0~10.0 and the amount of surfactant 0.2 mol·L-1. Meanwhile, the copper nanoparticles in ultrasonic field appeared smaller than usual. The prepared copper nanoparticles were characterized by XRD and SEM. The results showed that the product was pure copper powder, which had spherical morphology with nanoscale size. Under the optimum technological condition, the conversion ratio of copper ion in copperammonia waste water was more than 97% and the reaction product was nitrogen. After reaction, the reaction system composition had no variation compared with original liquid, due to no new metal ions being added during the reaction. The waste water after reaction can be returned to workshop as new alkaline etching liquor and green environmental protection realizes.