@article{Uzochukwu_Elijah_Enyinnaya_Chinenye_Michael_Mary_2023, title={Mathematical and Statistical Process Modeling of Hydrochloric Acid Leaching of Iron-Oxide Impurity from Inyi Kaolin: Response Surface Methodology}, volume={2}, url={https://journal.ijmdes.com/ijmdes/article/view/168}, abstractNote={<p>The iron-oxide impurity is comparatively abundant in the low-grade kaolin from Inyi in Enugu, Nigeria. The iron-oxide impurities in kaolin make it unsuitable for industrial use. This study focused on the mathematical and statistical process modeling of iron-oxide impurity leaching from Inyi Kaolin by hydrochloric acid (HCl). Response Surface Methodology (RSM) was used to examine the combined effects of leaching temperature, solid-liquid ratio, reaction time, stirring speed, particle size, and acid concentration on the removal of iron contaminant from the local kaolin in HCl. The second-order polynomial regression equation designed with a correlation coefficient R<sup>2</sup> of 0.9959 provided the best description for the experimental data. The leaching temperature of 79.99°C, the solid-liquid ratio of 0.021, and the reaction time of the leaching temperature was 79.99°C, the solid-liquid ratio was 0.021, the reaction duration was 240 minutes, the stirring speed was 580.985 rpm, the particle size was 0.045mm, the acid concentration was 3.513mol/cm<sup>3</sup>, and the yield was at its highest point of 94.35%.</p>}, number={8}, journal={International Journal of Modern Developments in Engineering and Science}, author={Uzochukwu, John Sunday and Elijah, Onu Chijioke and Enyinnaya, Ohale Pascal and Chinenye, N. Nweke and Michael, Madiebo Emeka and Mary, John Chioma}, year={2023}, month={Aug.}, pages={7–14} }