离子色谱法测定大气中的氮氧化物

Determination nitrogen oxides in air by ion chromatography

为简便、快速地测定空气中氮氧化物的含量，建立以内含质量分数为0．9％过氧化氢的混合溶液（混合溶液由2．2mmol／L的Na2CO3和2．7mmol／L的NaHCO。组成），混合溶液为吸收液，吸收大气中的氮氧化物，使大气中的氮氧化物全部转变为硝酸根。用离子色谱法测定表明，吸收剂中硝酸根在0．1～60μg／mL的浓度范围，峰面积与浓度之间呈良好的线性关系，回归方程为Y=779563X＋7021，相关系数为0．9996，检出限为0．002μg／mL。此方法简便、快速、准确、选择性好，对环境无二次污染，完全满足环境监测对大气中氮氧化物的测定。

An ion chromatographic method for determining oxides of nitrogen in air is described. The linear range is from 0.1 to 60 μg/mL with a detection limit of 0.01 g/5mL （nitrate in the absorbent）. The coefficient is 0. 9996 . The method is simple, rapid , accurate and sensitive , and agrees with the conventional spectrophotometric method for determining oxides of nitrogen. Nontoxic reagents are used, which are beneficial to environmental protection. That result proves that the proposed method can be used for environmental monitoring.