二正辛基亚砜萃取钯(Ⅱ)和金(Ⅲ)的动力学研究

Kinetic Studies on the Extraction of Palladium (Ⅱ) and Gold (Ⅲ) with Dioctyl sulfoxide

应用连续自动测定的恒界面池装置,研究了二正辛基亚砜(DOSO)在盐酸介质中萃取钯(Ⅱ)和金(Ⅲ)的动力学行为。得到了各自的萃取速率方程和表观活化能。测定了DOSO的两相分配和界面吸附性能。结果表明,DOSO萃取钯(Ⅱ)为界面配体取代反应控制类型,而萃取金(Ⅲ)则为扩散或混合控制类型。

The extraction kinetics of Pd(Ⅱ) and Au(Ⅲ) from HCl (1mol·dm^(-3)) medium with dioctyl sulfoxide (DOSO) were measured by the use of constant interfacial stirring cell which can measure the kinetic data continuously and autometically. The interfacial and distribution characteristics of DOSO as well as the influences of several parameters, such as stirring rate, concentration, temperature, and ratio between interfacial area and phase volume on the rate of extraction were studied. The results show that the extraction is controlled kinetically by interfacial chemical reaction regime (for Pd) and by diffusion or chemieal reaction-diffusion mixed regime (for Au) respectively. The difference of extraction kinetics between Pd(Ⅱ) and Au(Ⅲ) with DOSO has been explained.