Determination of Nitrite and Nitrate in Triethylenediamine Cobalt Solution

Rapid determination of nitrite and nitrate in triethylenediamine cobalt solution was established. Nitrate was detected by thymol method,and nitrite was measured by the improved GB 13580.7-92. Linearity range for nitrate was within 8 mg·L-1,and 0.03-0.8 mg·L-1 for nitrite. The correlation coefficients for nitrate and nitrite were 0.999 9 and 0.999 4,respectively. Values of recovery measured by standard addition method were in the range of 99.9%-108% for nitrate with RSD (n=7) of 1.2%. For nitrite,the recovery rates were 99.5%-107%,with RSD (n=7) of 1.4%.