测定亚硝酸根的表面活性剂增敏催化动力学光度法

Determination of Nitrite by Catalytic Kinetics Photometry with Surfactant Sensitizer

基于在稀硫酸介质中溴化十六烷基三甲基铵对ＮＯ２－催化溴酸钾氧化曙红褪色反应的作用，建立了测定ＮＯ－２的表面活性剂增敏催化动力学光度法。加入十六烷基三甲基溴化铵（ＣＴＭＡＢ）后体系最大吸收波长由４８０ｎｍ红移至５４０ｎｍ，ΔＡ增大约２０倍。ΔＡ与ＮＯ－２含量在００１～０２ｍｇ／Ｌ范围内存在线性关系，检出限为０００４ｍｇ／Ｌ。方法已用于水样中ＮＯ－２测定。

A catalytic kinetics photometric method for determination of nitrite with surfactant sensitizer has been developed.The method is based on that the color fadiny reaction of eosin Y oxidized by potassium bromate in the solution of dilute H 2SO 4 is catalyzed by nitrite,and cetyl trimethyl ammonium bromide(CTMAB) can be used as a sensitizer of the reaction.Added CTMAB in the system,the maxmum absorptive wavelength of the system shifted from 480 nm to 540 nm and Δ A increased by 20 times approximately.There is a linear relationship of Δ A with nitrite in the range of 0 01～0 2 mg/L.The detection limit is 0 004 mg/L.The method has been used to the determination of nitrite in water with satisfactory results.