When the irradiated uranium-aluminum alloy components are dissolved, in order to automatically adjust the amount of nitric acid during dissolving, and ensure dissolution go smoothly, it is necessary to rapidly analyze concentration of the aluminum. In acetic acidsodium acetate buffering system, the interference caused by a small amount of uranium and Hg2+ can be eliminated by adding a certain amount of Cl-. Through adding an excessive amount of disodium EDTA standard solution and selecting an appropriate indicator, Al3+ in this system can be determined indirectly with zinc standard solution which is used to back titrate EDTA in the experiment. And titration apparatus operated by manipulator, which is suited to be operated in hot cell, have been developed. For 1.6 mol/L Al3+ , the recovery of the results is 99. 47％-100. 56％, and the precision is better than 0. 36％. The analysis requirement of samples is satisfied.%溶解辐照过的铀、铝合金元件时,为了能自动调节溶解过程中的硝酸加入量,保证溶解过程的正常进行,需要对溶解液中的铝浓度进行快速分析.实验选择了醋酸-醋酸钠缓冲体系,使醋酸根掩蔽铀的干扰,并加入一定量的Cl-,消除少量汞(Ⅱ)的干扰,准确加入过量的EDTA二钠盐标准溶液,选择加入合适的指示剂,用锌标准溶液反滴定料液中的EDTA,间接测定了体系中的Al3+,并研制了适合于热室中机械手操作的滴定装置.对于1.6 mol/L AP+,分析结果的回收率为99.47%～100.56%,精密度优于0.36%,满足样品分析要求.
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