Abstract:

The kinetics of extracting boric acid from salt lake brine were investigated on the conditions of different initial concentrations of boric acid and 2-ethyl hexanol, temperature and the interfacial area of two-phase.The method of rising drop technique was used in the experiment with 2-ethyl hexanol as the complexing agent and toluene as a diluent.The result shows that the extraction rate of boric acid increases with the increasing of the initial concentrations of boric acid in the aqueous phase and 2-ethyl hexanol in the organic phase, the interfacial area of two-phase.The extraction reaction between boric acid and 2-ethyl hexanol is the quick reaction, which occurred in the interfacial area of two-phase.The extraction process is the diffusion-controlled mode by the calculation of the apparent activation energy.The kinetics equation of extracting boric acid with 2-ethyl hexanol regressed from the experimental data with the linear least square method can be expressed at pH=1(aqueous phase) and 318.15 K, and the relative deviation of rate constant is 5.318%.