Salting-Out Effect On Complexation Extraction Of Boric Acids From The Magnesium-Contained Brine

Taking the brine as raw material, Using 2-ethy-l-he.\anol as the complex agent and the aviation kerosene as the dilute, the salting-out effect of Mg on the process of extracting boric acids from the magnesium-contained brine were studied.In this paper, the salting-out effect of Mg on the process of extraction, the composition of complex were validated by the integral intensity method and the baseline method. The results showed: the complex were composed of monoisooctyl borate and diisooctyl borate, the monoisooctyl borate / diisooctyl borate ratio is 1.77:1. the reaction equilibrium constant of extracting boric acids were obtained, which K1 is 2.108, K2 is 1555The influential factors of salting-out effect, which contain the pH of the brine, the temperature of the system and the [Mg ], were studied. The results showed: the salting-out effect increased with the increasing [Mg ]; the salting-out effect kept invariant when pH is lower than 3.0; the salting-out effect reduced with the increasing of pH when the pH is between 3.0 and 5.0, the higher the [Mg ], the more obvious the influence; the pH almost has no influence on the salting-out effect when pH is higher than 5.0; the salting-out effect reduced with the increasing of temperature when the concentration of Mg is high and the pH is low, the higher the [Mg ], the faster salting-out effect decreases.Based on the experimental, the empirical regression formula for ionic hydration number of Mg was proposed. the results results showed: the error was about less than 6.40%.A salting-out effect model based on the extraction was established, the results showed: the error was about less than 10%, so this formula has be used in industrial process.