【摘要】 为测定空气中的微量NO2,提出一种新方法,即硅胶催化光度法。显色剂为对氨基苯磺酰胺和N-(1-萘基)-乙二胺盐酸盐,将其在硅胶颗粒介质中与NO2反应,生成玫瑰红色偶氮染料,在波长540nm下,测定其吸光度,从而计算NO2含量。将该方法与标准方法-Saltzman法进行对比。结果表明,在硅胶的催化作用下,显色反应的时间由Saltzman法的15min降至8min,分析测定的灵敏度也有所提高。该法操作简单方便,无干扰,用于测定空气样品中的微量NO2,结果较为满意。更多还原

【Abstract】 The paper is inclined to introduce its novel method for determining nitrogen dioxide (NO2) trace in the air based on the catalysis of the silica-gel, which actually involves the sulfanilamide, tartaric acid, EDTA and N-(1-naphthyl)-ethylenediamine dihydrochloride to form a rose red compound. The absorbency is determined at wave length 540 nm. The results of the trial use of the method indicate that the length of time to achieve the stable color can be reduced from 15 min to 8 min as compared with Saltzman method. The silica gel can not only help to catalyze the reaction process, but also contribute to increasing the sensitivity of the analysis. Thus, the proposed method proves to be simple and easy for its application and is thus expected to be applied for determining the trace amounts of NO2 with no interference in the air with satisfactory results being gained.更多还原