1980 Volume 29 Issue 6 Pages 410-412
A new method was proposed for the determination of nitrogen oxides in flue gases. A volume of 50 ml each of sample gases was introduced into a 100 ml syringe, followed by the addition of 20 ml of the alkaline absorption solution containing 0.03 % hydrogen peroxide and 30 ml of oxygen. After the completion of the (1520) min oxidation and absorption of nitrogen oxides, one ml of 6 N sulfuric acid was added to the absorption solution in order to decompose the excess of hydrogen peroxide by the careful addition of a 0.3 % solution of potassium permanganate. The pH range of the obtained solution was adjusted to 68 and the nitrate ions determined by the same analytical procedure as that of the zinc reductionnaphthylethylenediamine method. With the present method nitric oxide of about 85 ppm was successfully determined without any interferences of ammonia of up to 1000 ppm and of sulfur dioxide of more than 1000 ppm.
