催化共振光散射法测定空气中痕量甲醛的研究

吖啶橙分子聚集体微粒可在513nm波长处出现最大的共振光散射强度(RLS)。在稀硫酸介质中,甲醛能催化溴酸钾氧化吖啶橙的反应,促使其RLS强度减弱。在最佳实验条件下,甲醛质量浓度ρ在0.020～0.25μg/mL的范围内与△I值呈良好的线性关系,线性回归方程为△I=1113.99ρ+49.23,线性相关系数r为0.9986。本法与国标法进行对照,在置信度等于95%时,用Cochran检验,两种方法间不存在显著性差异,方法操作简单、灵敏度高,用于室内外空气中甲醛测定,结果满意。

Study and application of catalytic resonance lights cattering method for determination of trace formaldehyde in air

Acridine orange molecular aggregate particles can show the greatest resonance light scattering intensity(RLS) at the 513 nm wave edge. In dilute sulfuric acid media, formaldehyde can catalyze the reaction of potassium bromate oxide acridine orange, causing its RLS strength to weaken. Under the best experimental conditions, the formaldehyde concentration C had a good linear relationship with the△Ⅰ value in the range of 0.020-0.25 μg/m L, the linear regression equation was △Ⅰ = 1113.99 C+49.23, and the linear correlation coefficient rwas 0.9986. This method was contrasted with the national standard method.When the confidence level was equal to 95 %, there was no significant difference between the two methods. The method was simple and sensitive, and it was used for the determination of formaldehyde in indoor and outdoor air. The results were satisfactory.