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氮氧化物的分析最常用的是湿式化学分析法。用湿式化学法不能单独分析NO,只能测定NO_x。对于NO的化学分析法主要是三个步骤:第一步由于NO在水溶液中的溶解度极微,现在还未看到一种直接湿式化学法能分析NO。因此需首先将样品中的NO转化为能被水吸收的NO_2;第二步是气相氧化后进一步在液相氧化;第三步是在吸收完全后才进行NO_3~-或NO_2~-的分析。一般高浓度氮氧化物的标准测定法是苯酚二磺酸法(即PDS法),而日本JIS介绍作为NO及NO_2的标准气体浓度的测定法是采用Zn-还原法和中和滴定法。这三种方法其可靠性都很高。在研制高浓度氮氧化物标准气时对以上三种方法进行了实验,并用NO_x化学发光分析仪进行
The most common analysis of nitrogen oxides is wet chemical analysis. With wet chemical method can not separate analysis of NO, can only determine NO_x. There are mainly three steps for the chemical analysis of NO: The first step Since NO is extremely poorly soluble in aqueous solution, no direct wet chemical method has been found yet to analyze NO. Therefore, it is necessary to first convert the NO in the sample to NO 2 which can be absorbed by the water. The second step is the further oxidation in the liquid phase after the gas phase oxidation. The third step is to analyze the NO 3 - or NO 2 - after the absorption. The standard method for the determination of high concentrations of nitrogen oxides is the phenol disulfonic acid method (ie PDS method), while the Japanese JIS method for the determination of the standard gas concentrations of NO and NO 2 is the Zn-reduction method and the neutralization titration method. All three methods are highly reliable. In the development of high concentrations of nitrogen oxides standard gas when the above three methods were tested and NO_x chemiluminescence analyzer