HDEHP萃取Ga（Ⅲ）的动力学

The Extraction Kinetics of Ga(Ⅲ) with HDEHP

用生长液滴法研究了ＨＤＥＨＰ在盐酸介质中萃取Ｇａ（Ⅲ）的动力学，结果表明，萃取反应速率取决于发生在界面区域内两步连续反应Ｇａ３＋＋Ａｉ－＝ＧａＡｉ２＋ＧａＡｉ２＋＋Ａｉ－＝ＧａＡ２＋ｉ研究了阴离子表面活性剂ＳＤＳ、ＡＢＳ对ＨＤＥＨＰ萃取Ｇａ（Ⅲ）的影响，二者均不改变ＨＤＥＨＰ萃取Ｇａ（Ⅲ）的分配比，但使其正向萃取初始速率降低，原因是表面活性剂与萃取剂在界面上发生了竞争吸附；其次是表面活性剂的加入导致了界面膜上分子排列更致密和界面膜增厚，产生了更大的传质阻力。

The forward initial extraction rate of gallium(Ⅲ) with HDEHP has been measured by means of growing drop method at 298±1K.The experimental results indicate that the rate-determining step of the extraction process is controlled by interfacial reactions The addition of anionic surfactant(SDS,ABS) has no effect on the distribution ratio,but decreases the forward initial rate of extraction.Firstly,it is caused by the competitive adsorption of HDEHP,SDS and ABS on the interface.Secondly,surfactants bring about close molecular arrangement in the interfacial membrane and the thickening of membrane,producing greater mass transport resistance than in the absence of surfactants.