论文部分内容阅读
以对硝基苯胺为重氮化试剂和N-(1-萘基)乙二胺为偶联展色剂测定水中微量NO_2~-的偶氮染料法为基础,研究了生成的偶氮染料在不同酸度下,在不同溶剂中的溶解情况。实验比较了六种萃取方法,研究了在碱性条件下萃取油相的增色条件。实验证明,在碱性条件下,用三氯甲烷萃取生成偶氮染料,然后加入盐酸乙醇溶液增色是一种较好的方法。对水中含10~(-8)～10~(-10)数量级的NO_2~-,在2厘米比色池中及530毫微米波长下进行了测定,方法的最小检出浓度为1.4×10~(-10)。对浓度分别为2.00和20.0ppb的NO_2~-水溶液进行了分析,相对标准偏差分别为2.5和1.5%。测定一次的时间约45分钟。
Based on the azo dye method for the determination of trace amount of NO 2 - in water with p-nitroaniline as a diazotizing reagent and N- (1-naphthyl) ethylenediamine as coupling developer, the effects of the azo dyes Acidity, dissolved in different solvents. Six extraction methods were compared in experiments, and the conditions for the enhancement of oil phase extraction under alkaline conditions were studied. Experiments show that under alkaline conditions, chloroform extraction generated azo dyes, and then add hydrochloric acid solution of ethanol is a better method. The concentration of NO_2 ~ (10 ~ (-8) -10 ~ (-10)) in water was measured in a 2 cm cuvette and a wavelength of 530 nm. The minimum detectable concentration was 1.4 × 10 ~ (-10). The NO 2 - aqueous solutions at concentrations of 2.00 and 20.0 ppb were analyzed with relative standard deviations of 2.5 and 1.5%, respectively. Determination of a time of about 45 minutes.