铜的反萃取动力学研究

本文用NaCl-HCl水相进行了从负载HS-LIX65N有机相中反萃取铜的动力学研究.实验是在与萃取动力学研究所用的同一恒界面池(Lewis cell)内进行的.实验结果表明:铜的反萃速率几乎与两相内搅拌器的转速无关,但却正比于两相间的界面积,再加上测得的高活化能值,表明了铜的反萃过程具有明显的界面化学反应控制的特征.根据实验结果建立了经验数学模型,又按照带有吸附和解吸过程的界面化学反应控制机理和水膜内化学反应控制机理分析了这一反萃动力学的过程机制.数据处理表明:此过程具有“真正的界面化学反应”(即带有吸附和解吸过程的界面化学反应)控制的特征.其数学模型为:N_(Ca)=5.7×10~(-8)[(?)_2]_b~(0.884)[H~+]_b~(0.758)[Cl~-]_b~(0.906)式中浓度单位为mol/l,计算值与实验值的平均相对偏差为0.5%.应予指出:不能完全排除水相侧扩散膜内的界面化学反应对铜的反萃传质的贡献.

Studies on the Kinetics of Copper Stripping from Loaded HS-LIX65N

The kinetics of stripping copper from loaded HS-LIX 65N with NaCl-HC1 solution was carried out in a Lewis cell.Experimental results showed that the stirring speed of agitators in the two phases did not seem to have any significant effect on the stripping rate of copper. However, the stripping rate of copper was apparently almost proportional to the interfacial area between the two phases. In addition a relatively high value of apparent activation energy was apparent for the stripping process, featuring interfacial chemical reaction characteristics. Mathematical models were developed with experimental results obtained of which a typical one was given below:where, concentration was expressed in mol/l, and computational deviation wasfound to be around 0.5%.It was concluded, therefore, that the controlling regime in the systemwas the interfacial chemical reaction related with adsorption and desorption.