摘要
在稀H2SO4介质中,磷酸盐与钼酸盐和偏钒酸盐反应形成磷钒钼杂多酸,杂多酸再与孔雀绿缔合形成四元有色络合物,能稳定存在于含聚乙烯醇的水溶液中。缔合物的最大吸收位于590nm波长处,摩尔吸收系数ε=1.7×105L·mol-1·cm-1,P(V)的质量浓度在0～0.12μg mL范围内与吸光度成正比。研究了显色反应的适宜条件、共存离子的影响和缔合物的组成。方法已用于合成试样中磷的测定。
In H_2SO_4 containing polyvinyl alcohol, phosphate reacted with vanadate and molybdate to form P-V-Mo heteropoly acid. The heteropoly acid reacted with malachite green to form MV-P-V-Mo tetrabasic associated complex, leading to a color change of the solution. The wavelength of maximum absorption of the complex was at 590 nm, the molar absorption coefficient was 1.7×10~5 L·mol^(-1)·cm^(-1). The absorbance was directly proportional to the concentration of P(V) in the range 0～(0.12 μg/mL). Conditions of the chromogenic reaction, effects of some coexistent ion, and the formation of the complex were studied. The method was applied to the determination of P(V) in synthetic samples with satisfactory results.
出处
《分析试验室》
CAS
CSCD
北大核心
2004年第8期72-74,共3页
Chinese Journal of Analysis Laboratory
关键词
磷
磷钒钼杂多酸
甲基紫
吸光光度法
Phosphorus
P-V-Mo heteropoly acid
Malachite green
Spectrophotometry
