离子选择电极法测定铝土矿、赤泥中的氟

The Measuring of Fluorine in Bauxite and Red-mud with Ion Selection Electrode

试样经碱熔融浸取、过滤 ,使氟与铁、钛、稀土等氢氧化物分离 ,用乙酰丙酮 -氯仿混合萃取分离铝 ,在pH 5 5～pH 6 0的柠檬酸 -硝酸钾介质中 ,氟离子浓度在 0 μg5 0ml-1～ 10 0 μg5 0ml-1范围内呈线性关系 ,符合能斯特方程式 ,电极的响应斜率为 5 8 34(t=2 1℃ )。

Through fusing, leaching and filtering in aqueous alkali, the fluorine in test samples can be separated from hydroxides including Fe, Ti and rare-earth elements, etc.,and with 2,4-pentanedione -fluoform extraction Al can be separated.In the mediator of citric acid and nitrate of potash with pH value of 5.5-6.0, the concentration of fluorion appears linear relation in the scope of 0～100 pg/500 ml, which accord with Nernst Equation. And the response slope coefficient is 58.34(t=21?℃).