摘要
将钨钼矿石样品用氢氧化钠-过氧化钠混合熔剂在高温下熔融,加入沸水在超声辅助下浸提熔块,大量金属元素被沉淀除去。分取适量体积的上层清液,加入柠檬酸钠溶液调节离子强度,用酚红做指示剂,将溶液pH调节至7±0.2,用三乙醇胺为缓冲溶液,采用氟离子选择电极法进行测定。实验表明:人工计算和仪器直读两种方式测定结果无明显差异,仪器直读测定精密度稍好且测定的速度快;标准加入法和标准曲线法测定结果保持一致,方法无明显干扰,方法检出限为0.016%,测定范围为0.02%~10%。用钨钼矿石国家标准物质GBW07238、GBW07239、GBW07240和GBW07241来验证方法的准确度,测定值与推荐值相符,测定结果相对误差在-1.07%~1.15%,相对标准偏差在0.82%~1.64%。
Tungsten molybdenum ore samples were melted with sodium hydroxide sodium peroxide mixed flux at high temperature,boiling water was added,and the frit was extracted with the aid of ultrasound.A large number of metal elements were precipitated and removed.Take an appropriate volume of supernatant,add sodium citrate solution to adjust the ionic strength,use phenol red as indicator,adjust the pH of the solution to 7±0.2,use triethanolamine as buffer solution,and use fluorine ion selective electrode method for determination.The experimental results show that there is no significant difference between manual calculation and instrument direct reading,and the instrument direct reading has slightly better precision and faster speed;The results of standard addition method and standard curve method are consistent.The method has no obvious interference.The detection limit of the method is 0.016%and the determination range is 0.02%~10%.GBW07238,GBW07239,GBW07240 and GBW07241 are used to verify the accuracy of the method.The measured values are consistent with the recommended values.The relative error of the measured results is-1.07%~1.15%and the relative standard deviation is 0.82%~1.64%.
作者
陈小英
CHEN Xiao-ying(Lanzhou Institute of mineral exploration,Gansu Nonferrous Metal Geological Exploration Bureau,Lanzhou 730046,China)
出处
《世界有色金属》
2022年第17期148-150,共3页
World Nonferrous Metals
关键词
钨钼矿石
混合碱熔
离子选择电极法
Tungsten molybdenum ore
Mixed alkali melting
Ion selective electrode method
