The conditions for the efficient separation of tungsten(VI) and rhenium (VII) on alumina were established. The distribution coefficients K d for tungstate and perrhenate anions, as well as the separation factors α(α = KdWO42-/Kd ReO4-) were determined using hydrochloric or nitric acid as the aqueous media. Asolution of sodium chloride in the pH range 2–6 was also examined. Under all the tested experimental conditions, alumina is a much better adsorbent for tungsten than for rhenium. The obtained results indicated that the best separation of these two elements is achieved when 0.01– 0.1 mol dm-3HCl or 1.0mol dm-3 HNO3 are used as the aqueous media. If NaCl is used as the aqueous phase, the best separation is achieved with 0.20 mol dm-3 NaCl pH 4–6. Under these experimental conditions, the breakthrough and saturation capacities of alumina for tungsten at pH4 are 17 and 26 mg W/g Al2O3 respectively. With increasing pH, these values decrease. Thus, at pH 6 they are only 4 and 13 mg W/g Al2O3, respectively.
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机译：建立了在氧化铝上有效分离钨（VI）和rh（VII）的条件。使用盐酸或硝酸作为水性介质，测定钨酸根和高hen酸根阴离子的分配系数K d以及分离因子α（α= KdWO42- / Kd ReO4-）。还检查了pH范围为2–6的氯化钠溶液。在所有测试的实验条件下，氧化铝对钨的吸附剂比对rh的吸附剂要好得多。所得结果表明，当使用0.01–0.1 mol dm-3HCl或1.0mol dm-3 HNO3作为水性介质时，这两种元素的分离效果最佳。如果将NaCl用作水相，则使用0.20 mol dm-3 NaCl pH 4–6可获得最佳分离效果。在这些实验条件下，氧化铝在pH4下对钨的穿透能力和饱和能力分别为17和26 mg W / g Al2O3。随着pH值的增加，这些值会降低。因此，在pH 6时，它们分别仅为4和13 mg W / g Al2O3。
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