摘要
本文研究以钒(Ⅴ)作催化剂的 Mo(Ⅵ)-SCN^--RB^+-PVA_(124)超高灵敏显色体系和钼的分光光度测定条件。缔合物的吸收峰在588nm处,表观摩尔吸光系数高达2.0 x 10~7L·mol^(-1)·cm^(-1)。铜浓度在0～80ng/25ml 范围内符合比耳定律。并进一步研讨了本类显色反应的吸附机理.所制定的方法结合离子交换分离,已用于水样和麦饭石浸出液中钼的测定,结果较满意。测定下限可达0.1ppb(50ml 液样)
A superhigh sensitive spectrophotometric method was developed for the deter- mination of trace molybdenum,based on the formation of a complicated ion-association complex of molybdenum with rhodamine B(RB) and thiocyanate in the presence of polyv- inyl alcohol(PVA-124).V(V)was used to catalyze the reaetion of reducing Mo(Ⅵ)to Mo(Ⅴ)by thiocyanate.The ion-association complex exhibits maximum absorption at 588nm, its apparent molar absorptivity is 2.0×10~7 L.mol^(-1)·cm^(-1).Beer's law is obeyed in the range of 0～80ng/25ml for Mo(Ⅵ),The reaction mechanism has been discussed,the molar ratio of Mo to RB was found to be about 1:400 by molar absorptivity contrast method.The pro- posed method has been used for the determination of Mo in water and leaching solution of Maifan stone with satisfactory results.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1991年第5期514-518,共5页
Chinese Journal of Analytical Chemistry
关键词
钼
测定
超高灵敏
显色反应
Superhigh sensitive colour reaction
Molybdenum
Rhodamine B
