离子色谱-柱后衍生可见光检测环境空气中六价铬和废气中铬酸雾  

Determination of Chromium(Ⅵ) in Ambient Air and Chromium Acid in Exhaust by Ion Chromatography with Postcolumn Derivation Spectrophotometric Detection

作　　者：谢永洪[1] 王华清[1] 姚欢[1] 赵云芝[1] 钱蜀 

机构地区：[1]四川省环境监测中心站,成都610041

出　　处：《中国环境监测》2013年第6期128-133,共6页Environmental Monitoring in China

摘　　要：以硫酸铵-氨水溶液为淋洗液,二苯碳酰二肼为柱后显色剂,采用离子色谱-柱后衍生可见光检测环境空气中六价铬和废气中铬酸雾的含量.通过对分析条件的优化,建立了简便、灵敏、选择性好、准确性高和重现性好的分析气体中六价铬的方法.该方法在Cr6浓度1.00～600 μ.g/L之间线性良好,当采集50 L有组织废气和20 L无组织废气时,铬酸雾分析的检出限分别为2.2×10-5和1.1×10-5 mg/m^3,采集64 m^3环境空气时,Cr6分析的检出限为7.8×10-9 mg/m^3,以浸提后的样品水溶液连续进样得到其相对标准偏差为1.42％（n=8）.利用该法进行环境空气中六价铬和废气中铬酸雾的测定,回收率在80％ ～ 105％之间.监测结果显示：环境空气中六价铬含量处于极低状态;五金厂厂界废气中铬酸雾含量极低,约为5 tg/m^3;五金厂废气排气筒监测的气体中则含有较高浓度的铬酸雾,其含量已经超过GB 21900-2008中规定的排放限值.The concentration of Cr（Ⅵ.） in ambient air and chromium acid in exhaust by ion chromatography coupled with postcolumn derivation spectrophotometric detection,which was based on ammonium sulfate/ammonium hydroxide solution as eluent and diphenylcarbazide as color developing reagent.A simple,high selectivity,sensitive,accurate and high repeatability method was proposed to determine Cr（Ⅵ） in gas through the optimum of analysis condition.The linear range of the method was wide in the range of 1.00-600μg/L,detection limit for chromium acid analysis of 50L exhaust from stationary source and 20L exhaust acquired around the factory were 2.2 × 10-5 and 1.1 × 10-5mg/m^3,andS.8 × 10^-9 mg/m^3 for Cr（Ⅵ） analysis of64m^3 ambient air.The relative standard deviation of leach liquor was 1.42% （n =8）.The range of recovery was 80%-105% when applying this method to monitor the Cr（Ⅵ） in ambient air and chromium acid in exhaust,and the result showed that the Cr（Ⅵ） in ambient air was very low,the amount of chromium acid in exhaust from stationary source of a hardware products factory was high and exceed the limit value in GB 21900-2008,the amount of chromium acid in exhaust sampling around this factory was very low with about 5μ g/m^3.

关 键 词：离子色谱 柱后衍生 六价铬 环境空气 废气 

分 类 号：X830.2[环境科学与工程—环境工程]