Simultaneous Catalytic Spectro-photometric Determination of Nitrite and Nitrate in Flour and Water with Flow Injection Analysis
The nitrate content is an important factor for environmental water samples and flour.In a 0.35 mol/L H2SO4 solution,NO-2 has a strong catalyzing function on the decoloudzation of Gallocyanine (GC) oxidated by NaBrO3.Based on this,a novel method was developed to measure the NO-2 and NO-3 concentrations in water and flour.The flow injection technology was introduced into the analysis system.A single-valve dual- cingulums to inject which the Copperized-Cadmium slice and the reduction zone are isolated. The optimum solution for this method contains 1.48×10-4 mol/L GC,0.06 mol/L NaBrO3 and 0.2 mol/L of NH4Cl.Two empirical equations were proposed to calculate the NO-2 and NO-3 concentrations based on the measured signals.It can be used to measure NO-2 of from 0.001 mg / L to 2.0 mg/L and NO-3 of from 0.002 mg / L to 2.5 mg/L.The measurement frequency can be up to 20 samples / h.The relative standard deviation for eleven samples is less than 5%.
Flow injection analysis Nitrate content Water samples Flour
B.Q.Xiao
School of Civil & Envirement Engineering,University of Science and Technology,Beijing,China.
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
4363-4368
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）