石墨炉原子吸收光谱法测定奶粉中的六价铬  

Determination of Cr(Ⅵ) in Milk Powders by Graphite Furnace Atomic Absorption Spectrometry

作　　者：黄锋[1] 曹建国[1] 杨平华[1] 

机构地区：[1]云南省昭通市疾病预防控制中心,云南昭通657000

出　　处：《化工技术与开发》2014年第5期48-51,共4页Technology & Development of Chemical Industry

摘　　要：基于Cr（Ⅲ）与噻吩甲酰三氟丙酮（TTA）生成的络合物在石墨炉中的挥发性,建立一种前处理简单、灵敏度高的测定奶粉中六价铬的分析方法。对样品的消化方式、Cr（Ⅲ）与TTA络合的酸度、试剂的加入量、超声波水浴的温度和时间、静置时间与石墨炉挥发Cr（Ⅲ）的原子化条件进行探讨。结果表明,Cr（Ⅵ）在0.002-0.010mg·L^-1浓度内呈良好线性关系（r=0.9995）。奶粉样品中Cr（Ⅵ）不同加入量的平均回收率为78%-93%,其相对标准偏差为3.8%-9.4%,检出限为0.4 mg·L^-1。方法具有分析速度快、灵敏度高、干扰少、操作简便等特点,应用于奶粉中六价铬的测定获得了满意的结果。A novel and highly sensitive determination method of Cr（ Ⅵ） in milk powders was described based on the formation of a volatile complex Cr（ Ⅲ） and thnoyltrifl uroacetone. The manner of sample digestion,the reaction conditions of Cr（TTA）3 complex, such as the acidity, sonication time and temperature, the amount of reagent added and the time required for the complexation reaction were investigated. The atomization conditions to volatilize Cr（ Ⅲ） in graphite furnace were discussed. The calibration coeffi cient exceeds 0.9995 and the dynamic linear range was 0.001-0.010mg/L. The average recoveries of Cr（ Ⅵ） in milk powders was 78% - 93% with the relative standard deviations between 3.8%-9.4%, the limit of detection was 0.4 mg/L.

关 键 词：石墨炉原子吸收光谱法 Cr(TTA)3挥发 六价铬 奶粉 

分 类 号：O657.31[理学—分析化学]