Modeling of solvent sublation process and identification of parameters affecting the removal of Ni(II), Cu(II) and Fe(III) ions

Abstract

The solvent sublation method was used to remove Ni(II), Cu(II) and Fe(III) ions from wastewater. The purpose of this work was to develop a mathematical model of the solvent sublation process and identify the parameters that affect the degree of pollutant removal. The correlation analysis was used to evaluate parameters that influence on the process, and multiple correlation coefficient, Fisher's test and root-mean-square deviation were calculated to assess the adequacy of the suggested model. It was shown that such parameters as pollutant initial concentration, organic extractant type, the Me:surfactant ratio, temperature, and the process time have a significant impact on the solvent sublation process efficiency. The removal degree of the studied ions above 90% was achieved with the following parameters: pH of 9, 5 and 7 for solutions with Ni(II) ions, Cu(II) ions and Fe(III) ions, respectively; and Me:surfactant ratio of 2:1, 1.5:1 and 2:1 for solutions with Ni(II), Cu(II) and Fe(III) ions, respectively. The process time for all type of pollutants should be 15–20 minutes, and the initial concentration should be more than 100 mg/dm3. The results showed that the models successfully allows simulating the process efficiency and predicting Ni(II), Cu(II) and Fe(III) ions removal. The obtained results can be used to optimize the solvent sublation process as a technique for post-treatment of wastewater produced in electroplating industry.