室内空气中甲醛的快速测定

介绍了一种利用装有活化硅胶吸附剂的玻璃管吸附空气中的甲醛,然后加入显色剂B(KIO4),通过颜色比较,可快速检测甲醛含量的方法.其活化硅胶选为80～100目;其吸附剂组成为活化硅胶(碱性)和显色剂A(AHMT)的混合物.空气采样条件为:采气速率0.04L/min,采样量0.2L.采样后加入显色剂B,显色10min后和比色板比较确定甲醛含量.经初步试验,该玻璃检测管显色程度与甲醛的浓度具有较好的相关性(γ=0.9995)、检测重现性(不同浓度测定的相对标准偏差小于15%)和灵敏度(最低显色浓度为0.1mg/m3).可用于室内甲醛含量的快速检测.

RAPID DETERMINATION OF TRACE FORMALDEHYDE IN INDOOR AIR

This article affords a convenient method that combines activating silica gel absorbing trace formaldehyde and the show compound B(KIO_4) to determine the content of formaldehyde in air quickly. The experimental conditions are as follows: the carrier is active silica gel of 80～100 mesh, the sorbent consist of activating silica gel(alkalescence)and show compound A(AHMT), the conditions of sampling air are the sampling speed and volume are 0.04 L/min and 0.2 L respectively. Then add show compound B to the sample, color development time is 10 min, and then comparing the color change, we further deduce the content of formaldehyde. The results obtained show that the color degree of the glass tube has a high correlation to the concentration of HCHO (γ=0.999 5), furthermore, the method reaches fine repeatability (relative standard deviation in different concentration of formaldehyde less than 15%)and high sensitivity (the least of showing color concentration is 0.1 mg/m~3). The method, which is convenient for the determination of the concentration of HCHO in air, is suitable for using at home.