| 摘要 |
PURPOSE:To measure an extreme trace of nitrogens in the forms of ammonia, nitric (nitrous) acid and organic compound quickly at a high accuracy by combining two sets of distillating sections and measuring sections free from effect or water. CONSTITUTION:A sample water injected into an injection port 5 is reacted with H2 gas introduced from an introduction tube 34 at a reaction section 33 to reduce N compound therein to NH3, which is absorbed with an absorbing liquid in an electrolytic cell 27 via an oxygen gas removing section 30 and conduits 28 and 26 and undergoes a coulometric titration to measure the N compound. Then, the sample water is fed to a distillation cell 19 of a distillation section 2 to turn the nitrogen in the form of nitrous acid to NO or NO2, which is introduced into the reaction section 33 with a carrier gas introduced from a introduction tube 17 via a reflex condenser 7 and a conduit 6. Thereafter, following the same procedure with the N compound, the nitrogen in the form of nitrous acid is measured. The sample water undergoes a reduction treatment to turn the nitrogen in the form of nitric acid to nitrous ion. Thereafter, according to the same procedure with the nitrogen in the form of nitric acid is measured. The sample water is also fed to a distillation cell 12 of the distillation section 4 to be turned to NH3, which is sent to an electrolytic cell 23 with a carrier gas via a reflux condenser 9 to measure the nitrogen in the form of ammonia. |
