Preparation of high purity copper sulfate from semiconductor waste electronic grade sulfuric acid

With the rapid growth of the electronics industry, the consumption of electronic-grade sulfuric acid has surged. The amount of produced waste sulfuric acid is 1.2-1.5 times greater than that of electronic-grade sulfuric acid. In this study, waste electronic-grade sulfuric acid was purified and synthesized to produce electroplating-grade high-purity copper sulfate. Specifically, the polysulfides in waste electronic-grade sulfuric acid were targeted converted through electrochemical methods, reducing their concentration from 4.848% to 0.284%. Subsequently, the treated waste electronic-grade sulfuric acid was utilized for the preparation of high-purity copper sulfate. And a comparative study was undertaken to evaluate two technical approaches: chemical synthesis and electrochemical preparation. The investigation revealed that both the copper oxide synthesis method and the electrochemical preparation method can produce high-purity sulfuric acid. However, the purity of copper sulfate achieved through electrochemical processes is notably higher. This method accomplishes the high-quality cascade utilization and recycling of sulfur resources.