Manufacture of Ultra Fine CuO Powder from Waste Copper Chloride Solution by Spray Pyrolysis Process

Abstract

ABSTRACT The main purpose of this study is to generate a fine copper oxide powder, with a compact structure and a uniform particle size by a spray pyrolysis process. The raw material is a waste copper chloride solution formed in the manufacturing process of Print Circuit Board (PCB). This study also examines the influences of various factors on the properties of the generated powder. These factors include the reaction temperature, the inflow speed of the raw material solution, the inflow speed of the air, the size of the nozzle tip, and the concentration of the raw material solution. It is discovered that, as the reaction temperature increases from 800°C to 1000°C, the particle size of the generated powder increases accordingly, and that the structure of the powder becomes much more compact. When the reaction temperature is 1000°C, the particle size of the generated powder increases as the concentration of copper in the raw material solution increases to 40 g/L, decreases as the concentration increases up to 120 g/L, and increases again as the concentration reaches 200 g/L. In the case of a lower concentration of the raw material solution, the generated powder appears largely in the form of CuO. As the concentration increases, however, the powder appears largely in the form of CuCl. When the concentration of copper in the raw material solution is 120 g/L, the particle size of the generated powder increases as the inflow speed of the raw material solution increases. When the concentration of copper in the raw material solution is 120 g/L, there is no evident change in the particle size of the generated powder as the size of the nozzle tip and the air pressure increases. When the concentration is 40 g/L, however, the particle size keeps increasing until the air pressure increases to 0.5 kg/, but decreases remarkably as the air pressure exceeds 0.5 kg/