动力学催化光度法测定痕量亚硝酸根  

KINETIC PHOTOMETRIC DETERMINATION OF TRACES OF NITRITE

作　　者：王瑜[1] 

机构地区：[1]沧州师范专科学校化学系,沧州061001

出　　处：《理化检验（化学分册）》2005年第8期561-562,568,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：基于硫酸介质中亚硝酸根催化溴酸钾氧化间甲酚紫的褪色反应,建立了测定痕量亚硝酸根的新方法,并探讨了动力学条件,测定了反应的表观速率常数(k′=1.03×10-4s-1)和表观活化能(E′a=10.25kJ·mol-1).方法的测定范围为8.0～150μg·L-1,检出限为0.9μg·L-1.方法已用于水样中亚硝酸根的测定.A new method for the determination of nitrite was established on the basis of the fact that the decoloration of m-Cresol purple, which was resulted by the oxidation by bromate, was catalyzed by nitite in H2SO4 medium. Kinetic conditions were studied. Apparent reaction rate constant （k＇ = 1. 03 × 10^-4 s^-1 ） and apparent activation energy （E＇a =10. 25 kJ· mol^- 1 ） were determined. Determination range of the method was 8. 0-150 μg·L^-1 and detection limit 0. 9 μg · L^-1 for nitrite. The method has been applied to the determination of nitrite in water samples.

关 键 词：动力学催化光度法 间甲酚紫 溴酸钾 亚硝酸根 

分 类 号：O657.31[理学—分析化学]