Determination of nitrite nitrogen in water by UV-1100 spectrophotometry

Determination of nitrite nitrogen in water by diazotization coupled spectrophotometry Keywords: spectrophotometer; nitrite nitrogen in water; analysis instrument ; V-1100; V-1200 experimental method: 1, if water sample For turbidity or darkness, take 100ml first, add 2ml aluminum hydroxide suspension, stir and let stand for several minutes to filter. 2. First adjust the water sample or the treated water sample to neutral with acid or alkali, and take 50.0ml in the colorimetric tube. 3. Add 1 ml of p-aminobenzenesulfonamide solution (10 g/L) to the water sample, shake and place for 8 minutes. Add 1.0 ml of N-(1-naphthyl)-ethylenediamine hydrochloride solution (1.0 g/L) and mix immediately. 4. At a wavelength of 540 nm, a 1 cm cuvette was used as a reference for pure water, and the absorbance was measured after 10 minutes. 5. Calculate C _NO2-N =M/VC _NO2-N —Nitrite nitrogen concentration in water sample, mg/LM—Check the nitrite nitrogen content in the sample tube from the calibration curve, ugV—water sample volume, ml Key words: spectrophotometer; nitrite nitrogen in water; US analytical instrument ; V-1100; V-1200