水杨基荧光酮分光光度法测定聚丙烯及润滑油中微量锡

在十二烷基硫酸钠存在下 ,Sn 与水杨基荧光酮在强酸性介质中 ,生成高灵敏度的三元络合物 ,摩尔吸收系数ε5 35nm=1.4× 10 5 ,线性范围 0～ 12.0 μg/ 2 5mL。此显色体系已成功地用于测定聚丙烯及润滑油中微量锡。对测定条件、灰化条件、熔剂的选择及干扰的消除进行了考察。硫酸钠既可作为润滑油的助灰化剂加速灰化速度 ,同时还是锡的固定剂 ,防止锡的损失。加标回收率 10 0.2 %～ 10 1.2 %。方法简便、灵敏。

Spectrophotometric determination of micro tin in polypropylene and lubricating oil with salicylfluorone

In the presence of sodium dodecyl sulphate(SDS), a highly senitive ternary complex of tin　with salicylfluorone was formed in the strong acidic medium. The apparent molar absorption coefficient ε499nm was 1.4×105L*mol-1*cm-1. The linear range was 0-12μg/25m L. This coloured system was used to determine successfully tin in polypropylene and lubricating oil. The determing and ashing conditions, choice of melting agent and elimination of interference were studied. Sodium sulphate could be regarded as a helping ashing agent for lubricating oil to accelerate ashing speed, also as a fixed agent for tin to prevent evaporating and losing tin. The recoveries of standard addition were 100.2%-101.2%. This method was simple, easy to operate and sensitive.