摘要
本文研究了在聚乙烯醇（ＰＶＡ）存在下用钼酸盐与乙基罗丹明Ｂ（ＥＲＢ）形成离子缔合物，该缔合物的最大吸收位于５８０ｎｍ，摩尔吸光系数为１．１２×１０６Ｌ·ｍｏｌ－１·ｃｍ－１，服从比耳定律范围０—２．５μｇ／２５ｍＬ，缔合物至少稳定１周，考察了５０多种共存离子的影响，除生成杂多酸元素和Ａｕ（Ⅲ）、Ｏｓ（Ⅷ）、Ｐｄ（Ⅱ）、Ｉｒ（Ⅳ）外，大多数元素不干扰。测定铂的条件为：〔ＨＣｌＯ４〕＝１．２ｍｏｌ／Ｌ，〔ＭｏＯ４２－〕＝９．１×１０－４ｍｏｌ／Ｌ，〔ＥＲＢ〕＝３．２×１０－５ｍｏｌ／Ｌ，０．０８％ＰＶＡ。缔合物的摩尔比为Ｐｔ（Ⅳ）∶ＥＲＢ＝１∶２，本法已用于铂矿中铂的测定，结果满意。
Platinum(Ⅳ)reacts with ammonium molybdate and ethyl rhodamine B(ERB)to form a ion associated complex has been studied in the presence of polyvinyl alcohol(PVA).Its apparent molar absorptivity is 1.12×10 6L·mol -1 ·cm -1 at 580nm.Beer's low is obeyed in the range of 0 to 2.5μg/25mL for platinum. The ion associated complex is stable for at least 1 week.The influence of diverse 50 ions was examined. Most ions do not interfere except gold(Ⅲ), osmium(Ⅷ),palladium(Ⅱ),iridium(Ⅳ)and those elements which can form heteropoly acid. The optimum conditions for determination of platinum are =1.2mol/L,[MoO 2- 4]=9.1×10 -4 mol/L,=3.2×10 -5 mol/L and PVA0.08%.The molar ratio of Pt(Ⅳ) to ERB in the ion associated complex was established to be 1∶2. The method is satisfactorily applied to the determination of platinum in some minerals.
出处
《光谱实验室》
CAS
CSCD
1998年第2期48-51,共4页
Chinese Journal of Spectroscopy Laboratory
