Kinetic constant modeling of Zn(II) ion removal from synthetic wastewater by gene expression programing

The separation of ions from wastewater and environments such as hydrometallurgy has been a major challenge in the development of ion flotation in recent years. A few studies have been carried out on the kinetics of metal ion removal by ion flotation. In this study, a new model using gene expression programming (GEP) method is proposed to predict the kinetic constant of zinc ion removal (k-Zn(II)) from synthetic wastewater with sodium dodecyl sulphate as collector. The efficiency of ion flotation is depends on both the amount of ion removal and water removed during the process. In this regard, the water removal kinetics constant (k-W) was also investigated. The effect of important parameters on k-Zn(II) and k-W including the ratio of SDS/Zn(II), the activity coefficient and the pH were investigated. The values of R2, RMSE and VAF of the GEP models for the testing data for k-Zn(II) were 0.98, 0.66, and 98.9 and for water removal they were 0.94, 0.004 and 0.93, respectively. The results indicate the higher performance of GEP models for the prediction of k-Zn(II) and k-W. The sensitivity analysis of GEP models showed that k-Zn(II) and k-W are more sensitive to pH and the ratio of SDS/Zn(II), respectively.