China Nonferrous Metallurgy

To address the high cost of single-factor process experiments and Design-Expert software, this study investigates the sulfuric acid leaching of high-clay copper oxide ore. A central composite design (CCD) was employed to conduct 20 sets of acid leaching experiments. With sulfuric acid concentration, liquid-to-solid ratio, and leaching time as independent variables, and copper leaching rate as the response value, a quadratic regression model was established using Excel. Analysis of variance (ANOVA) and response surface optimization were performed to determine the optimal solution. The results show that the model is highly significant (F = 91. 14, R2 = 0. 988). The influence of factors on the leaching rate follows the order: sulfuric acid concentration > leaching time > liquid-to-solid ratio. The interaction between sulfuric acid concentration and liquid-to-solid ratio exhibits a significant negative effect. The optimal process conditions obtained from the response surface optimization are: sulfuric acid concentration of 96. 16 g/L, liquid-to-solid ratio of 3. 26 mL/g, and leaching time of 4. 32 h, with a predicted leaching rate of 83. 39%. A verification experiment yielded a leaching rate of 84. 15%, showing good agreement with the prediction, indicating the predictive accuracy of the model and the reliability of the optimization results. By replacing professional statistical software with Excel, this method not only provides an efficient parameter optimization strategy for the sulfuric acid leaching process of high-clay copper oxide ore but also offers a cost-effective and easy-to-operate solution for process optimization in mineral processing and other related fields.