论文部分内容阅读
该文叙述了用涂有三辛基氧化膦(简称 TOPO)的玻璃态碳(简称 GC)电极伏安法测定核化工过程中废液中痕量铀。在测定之前,将铀酰离子预先浓集在 GC 电极 TOPO 涂层上。为得到这种涂层电极,将2.5微升的 TOPO 酒精溶液(1.5×10~(-2)M)移放在 GC 电极的圆形(直径7毫米)截面上,然后用红外线烘熔。这种电极,在开路状况下能有效地从溶液(0.25M,pH为3.4的 KNO_3)中浓集痕量铀酰离子。被浓集的铀酰离子在约-0.35伏(对甘汞)处产生一还原波,波高与溶液中铀酰离子浓度存在依赖关系。该方法对铀酰离子具有很高的选择性,因 TOPO涂层能掩蔽在电化学上电极没有这种涂层而能在电极上产生还原波的一些离子。该方法还具有灵敏度高、简单、快速等优点.
This paper describes the voltammetric determination of trace uranium in waste water of nuclear chemical industry by glassy carbon (abbreviated as GC) electrode coated with trioctylphosphine oxide (abbreviated as TOPO). Prior to the assay, uranyl ions were pre-concentrated on the GC electrode TOPO coating. To obtain this coated electrode, 2.5 μl of TOPO alcohol solution (1.5 × 10 -2 M) was transferred onto a circular (7 mm diameter) cross-section of the GC electrode and then bake by infrared rays. This electrode, in the open-circuit condition, effectively concentrates trace amounts of uranyl ions from solution (0.25 M, pH 3.4 KNO 3). The concentrated uranyl ions produce a reduction wave at about -0.35 volts (for calomel) with a dependence on the concentration of uranyl ions in solution. This method is highly selective for uranyl ions since the TOPO coating masks some of the ions that produce a reducing wave on the electrode without the coating on the electrochemical top electrode. The method also has the advantages of high sensitivity, simple, fast and so on.