环境水质中微量亚硝酸盐氮的测定

摘要

在酸性条件下,亚硝酸盐氮（NO2--N）可与沙黄生成蓝紫色配合物,在H3PO4介质中,其显色体系的最大吸收波长为597 nm,表观摩尔吸光系数为3.97×103L/（mol.cm）,在ρ（NO2--N）=0μg/L～1 900μg/L时,遵守比耳定律。该方法用于环境水样中微量亚硝酸盐氮的测定,结果与经典的盐酸萘乙二胺比色法基本一致。%A method based on the spectrophotometrie system of nitrite-N have been developed for the determination of nitrite in this paper. In the presence of H3PO4, the maximum absorption wavelength is 597 nm and the apparent molar absorptivity is 3.97 × 10^3 L/(mol . cm). Beer's law was obeyed in the concentration range of 0 ug/L - 1 900 ug/L. This method has been applied to the determination of micromount of nitrite in environmental water and the obtained results are in agreement with that of the N-( 1-naph- thyl)-ethylenediamine dihydrochlofide photometric method.