Toyoaki Aoki

Continuous flow method for simultaneous determination of nitrate and ammonia in water

A new continuous flow procedure is proposed for the simultaneous determination of nitrate and ammonia in water. Ammonia is fluorometrically determined with o-phthalaldehyde reagent, and nitrate is determined after reducing it to ammonia in alkaline medium by titanium-(III) chloride. The ammonia generated in alkaline sample solution is separated with a tubular microporous PTFE membrane. Nitrite stoichiometrically interferes with the present method but can be masked by sulfanilic acid. Detection limits (S/N = 3) for nitrate and ammonia were 1.8 x 10/sup -7/ and 1.8 x 10/sup -8/ M, respectively. Nitrate and ammonia in rivers were simultaneously determined with satisfactory results. 12 references, 3 figures, 4 tables.

Determination of total nitrogen in water by chemiluminescence method; Comparison of catalysts.

高価な白金触媒を用いることなく,実験室で簡易に調製した種々の触媒を用いて,水中の全窒素の化学発光による測定の基礎検討を行った.キャリヤーとして酸素を用い,900℃の燃焼温度でMnO2,CuO,Fe2O3のいずれの触媒を用いた場合も0.2~280N-ppmの間で検量線は直線となり,検出限界(S/N=3)としては,それぞれ0.08,0.11,0.17N-ppmで,MnO2を用いた場合がわずかに優れていた.