分光光度法测定茶叶中微量铅（Ⅱ）  

Determination of trace lead in tea by spectrophotometry

作　　者：张先廷[1] 

机构地区：[1]忻州师范学院专科部,山西忻州034000

出　　处：《山西化工》2012年第5期53-55,共3页Shanxi Chemical Industry

摘　　要：用三氯甲烷作萃取剂,通过Pb2＋和双硫腙的配位显色反应,研究了茶叶中微量铅含量的测定方法。实验结果表明,在pH=10.5的三酸缓冲溶液中,有色溶液的最大吸收波长为510 nm,Pb2＋质量浓度在0 mg/L～2.0 mg/L符合朗伯-比尔定律,加标回收率为98.9%～102.2%,重现性较好。本法用于测定茶叶中的Pb（Ⅱ）,简单易行、结果可靠。The determination method of trace lead content in tea was studied by Pb^2＋ and diphenylthiocarbazone matching place coloration reaction which uses trichloromethane as extraction agent. The results show that, in pH = 10.5 britton-robinson buffer solution, colouted solution maximum absorbs wavelength being 510 nm, Pb^2＋ concentration accords with lambert-beer law within 0 mg/L - 2.0 mg/ L range , add the bid coefficient of recovery is 98.9% - 102.2% , and reappearance is better. This law used for Pb^2＋ in determine tea is simple and reliable.

关 键 词：茶叶 铅 双硫腙 分光光度法 

分 类 号：TQ123.4[化学工程—无机化工] O644.1[理学—物理化学]