关键词：
湿消化;双硫腙;目视比色法;饲料;铅测定
摘 要：
建立了对饲料中铅含量测定的HNO3-HClO4湿消化的三氯甲烷萃取的双硫腙目试比色法。样品用HNO3+HClO4湿消化并消除干扰离子后,加入双硫腙的三氯甲烷溶液,根据铅与双硫腙生成的络合物在有机溶剂中的颜色深浅与铅含量在一定范围内成正比的关系,用目视比色法即可快速判断出样品中的铅含量。结果表明,改进后的方法,既不使用任何光学仪器,也不需要配制标准系列色阶,其操作简单、快速、准确、省时,测定结果的相对偏差(RD)<4.0%,相对标准偏差(RSD)仅为2.4%,可满足国家标准的限量要求。是一种快捷、灵敏、高效的测定饲料中微量铅的方法。
译 名：
Rapid Determination of Trace Lead in the Feed with HNO_3-HClO_4 Wet Digestion by Visual Colorimetric of Dithizone
作 者：
WANG Jian-guo et al(School of Chemistry and Chemical Engineering,Yulin College,Yulin,Shaanxi 719000)
关键词：
Wet digestion;Dithizone;Visual colorimetric;Feed;Determination of lead
摘 要：
An analytical method of trace lead in the feed with HNO3-HClO4 wet digestion by chloroform extraction and visual colorimetric of dithizone was researched in this paper.After the sample was digested with HNO3-HClO4 and the disturbance was eliminated,then dithizone and chloroform solution were added in the sample.According to the direct ratio relationship in a certain range between the color degree of the organic solvent with Pb2+ and the dithizone in the complex compound and the amount of the lead,the amount of the lead can be rapidly determined by way of the visual colorimetric.The results showed that with the improved method there was no optics instrument and standard color gradation in use.This approach was simple,fast,accurate and time-saving.The relative deviation of determination result was <4.0% and RSD was only 2.4%,which met the requirement of the national standard.This was a fast,ingenuity and high efficiency method in the determination of the trace lead in feed.
