摘要
研究了以熔融萘作为萃取剂,以4,7 二苯基 1,10 菲口罗啉作为显色剂,测定天然水中微量铁的分光光度法。在pH4的条件下,铁(Ⅱ)与4,7 二苯基 1,10 菲口罗啉和四苯硼酸盐能够形成红色三元络合物。在熔融萘存在下,此络合物可以迅速萃入熔融萘。将含有络合物的萘冷却、固化、分离,配制成25mL丙酮溶液,对其进行分光光度分析。实验表明,该络合物最大吸收波长为534nm,摩尔吸光系数和桑德尔灵敏度分别为2×104L·mol-1·cm-1和0.0025μg/cm2,铁(Ⅱ)的质量浓度在0~2 0μg/mL的范围内符合比耳定律。大多数常见离子不干扰测定。已应用于天然水中微量铁的测定。
The method for the spectrophotometric determination of iron after extraction of its ternary complex with 4,7-diphenyl-1,10-phenanthroline and tetraphenyborate into molten naphthalene was studied. Iron(Ⅱ) reacted with 4,7-diphenyl-1,10-phenanthroline and tetraphenyborate to form a stable red ternary complex, which was easily extracted into molten naphthalene at pH 4. The solid naphthalene containing the ternary complex was separated by filtration and dissolved in acetone. The absorbance was measured at 534 nm against a reagent blank. Beer′s law was obeyed in the concentration range of 0~50 μg of iron in 25 mL acerone solution. The molar absorptivity and Sandell′s sensitivity at 534 nm was 2×10~4 L·mol^(-1)·cm^(-2) and 0.0025 μg/cm^2, respectively. The interference of various ions was studied in detail. The method was applied to determine micro amounts of iron in natural water samples with satisfactory results.
出处
《分析试验室》
CAS
CSCD
北大核心
2004年第9期48-50,共3页
Chinese Journal of Analysis Laboratory
关键词
熔融萃取
萘
4
7-二苯基-1
10-菲啰啉
四苯硼酸盐
光度法
Molten extract
Naphthalene
Iron
4,7-diphenyl-1,10-phenanthroline
Tetraphenylborate
Spectrophotometric