【摘要】 本文研究了新显色剂2-(4-氯-2-胂酸苯偶氮)-7-(2,4-三溴苯偶氮)-1,8-二羟基-3,6-萘-二磺酸(CAsA-TB)与钍的显色反应。研究结果表明,在强酸介质中形成稳定的紫红色配合物,最大吸收波长为645nm,表观摩尔吸光系数为1.3×10~5,钍浓度在0～15μg/25ml范围内遵守比耳定律。反应的选择性好,铀、钛、重稀土的选择性大,常见金属元素如钙、镁、铁、镉、镍、钴、铜、钡、钼等均不干扰测定。用于钨钍合金中微量钍的测定,结果满意。更多还原

【Abstract】 In this paper. a new Chromogenic reagem 4-chloro-arsenazo-TB is reported and its chromogenic reaction with thort-um has heen studied. In a strong acid medium. CAsA TB reacts with Th(Ⅳ) to form a stable complex of viclet red colour. Tlu absorption maxium of this complex lies at 645nm with an apparent molar absorptivity of 1. 3×10~5. Beer’ s law is obeyed in th?tration range of 0～15mg/25ml for Th (Ⅳ). Uranium(Ⅵ). Ti (Ⅳ). heavy rare carths and most of other common metal ions do notinterfere. This method has been applied to the determination of Th in W-Th alloys with satisfactory results.更多还原