【摘要】 <正> 测定水中痕量铀往往需预富集。见诸文献的已有溶剂萃取、共沉淀、胶体浮选、离子交换,以及螯合树脂、活性炭和硅胶吸附等法。用试剂负载泡塑萃取富集铀未见报道。本文研究了用氯化三辛基甲基铵（N-263）负载聚氨酯泡沫塑料从水中萃取富集痕量铀（Ⅵ）;系统考察了振荡平衡时间、酸度、硫氰酸钾浓度、铀（Ⅵ）浓度、共存离子等萃取参数的影响;在最佳萃取条件下,ppb-ppm级铀（Ⅵ）可从pH₂.0的0.5M KSCN介质中萃取回收90％左右,表观分配比达3.1×10⁴以上,富集因子1800以上。用此新法预富集,再用偶氮肿Ⅲ光度测定水样中痕量铀（Ⅵ）,结果满意,测定下限低至xμg/l.方法简单、快速、灵敏、无溶剂污染。更多还原

【Abstract】 The effects of equilibrium time, pH of aqueous phase, concentration of KSCN and U(Ⅵ), and foreign ions on the extraction were examined. If phase ratio was 1:2000, and shaking time was over 40 min at room tempe-rature, trace U(Ⅵ)at ppb levels could be almost quantitatively extracted by the N-263-loaded foam in 0.5M KSCN medium at pH 2.0 and the distri-bution ratio was over 3.1×10~4. A new and rapid technique for preconcen-tration and extraction-spectrophotometric determination was developed for U(Ⅵ)at ppb level in bulky water samples.更多还原