摘要
为实现铀矿地质样品氧化-还原电位的准确测定,对比分析酸性重铬酸钾法和碱性高锰酸钾法在铀矿地质样品氧化-还原电位测定中的应用效果,探寻更优的测定方法与实验条件,本研究采用电位落差法,系统地对酸性重铬酸钾法和碱性高锰酸钾法进行多维度对比,包括溶液稳定性、最佳溶液浓度、样品浸泡时长、固液比和电极平衡时间。碱性高锰酸钾法的样品浸泡时间和电极平衡时间比酸性重铬酸钾法短,能更快达到稳定可靠的电位值。针对强还原性样品,酸性重铬酸钾法所得ΔEh值更大,但两种方法对样品还原能力大小的评价结论一致。碱性高锰酸钾法的精密度更优。碱性高锰酸钾法的最佳实验条件为:浓度0.03 mol·L^(-1),样品浸泡1.5 h,固液比1∶25,电极平衡时间5 min,反应介质为0.2%氢氧化钾溶液,温度(25±1)℃。采用该方法测定的ΔEh值与氧化系数法(Fe^(2+)/Fe^(3+))对氧化-还原环境的判定结果基本一致,且与样品颜色基本吻合。综合各项实验指标,碱性高锰酸钾法在铀矿地质样品氧化-还原电位测定中整体性能优于酸性重铬酸钾法。采用最佳实验条件,实现了对铀矿地质样品氧化-还原电位的准确测定,为铀矿地质研究提供了可靠的技术支撑。
To accurately measure the oxidation-reduction potential of uranium ore geological samples,this study try to explore a better measurement method and experimental conditions by comparing and analyzing the application effects of the acidic potassium dichromate method and the alkaline potassium permanganate method in the measurement of the oxidation-reduction potential of uranium ore geological samples.The potential drop method was used to systematically conduct a multi-dimensional comparison between the acidic potassium dichromate method and the alkaline potassium permanganate method.The aspects of comparison included solution stability,optimal solution concentration,sample soaking time,solid-liquid ratio,and electrode equilibrium time.The sample soaking time and electrode equilibrium time of the alkaline potassium permanganate method are shorter than those of the acidic potassium dichromate method,allowing it to reach a stable and reliable potential value more quickly.For strongly reducing samples,theΔEh value obtained by the acidic potassium dichromate method is larger.However,the evaluation conclusions of the two methods regarding the reduction ability of the samples are consistent.Nevertheless,the precision of the alkaline potassium permanganate method is better.The optimal experimental conditions for the alkaline potassium permanganate method are as follows:a concentration of 0.03 mol∙L^(-1),a sample soaking time of 1.5 h,a solid-liquid ratio of 1:25,an electrode equilibrium time of 5 min,a reaction medium of 0.2%potassium hydroxide solution,and a temperature of(25±1)°C.TheΔEh value measured by this method is basically consistent with the judgment results of the oxidation-reduction environment by the oxidation coefficient method(Fe^(2+)/Fe^(3+)),and is also basically consistent with the color of the samples.Based on comprehensive experimental indicators,the overall performance of the alkaline potassium permanganate method is superior to that of the acidic potassium dichromate method in the measurement of the oxidation-reduction potential of uranium ore geological samples.By adopting the optimal experimental conditions,the accurate measurement of the oxidation-reduction potential of uranium geological samples is achieved,providing reliable technical support for uranium ore geological research.
作者
张建梅
邓长生
乔浩
ZHANG Jianmei;DENG Changsheng;QIAO Hao(Geologic Party No.216,CNNC,Urumqi 830011,China)
出处
《世界核地质科学》
2025年第3期647-658,667,共13页
World Nuclear Geoscience
基金
中国核工业地质局项目“新疆察布查尔县都拉塔地区铀矿普查(编号:202305-1)”资助。
关键词
电位落差法
氧化-还原电位
碱性高锰酸钾
酸性重铬酸钾
铀矿地质样品
potential drop method
redox potential
potassium permanganate
potassium dichromate
geological samples of uranium ore
