摘要
铅锌矿样经盐酸和硝酸溶解后,以硫酸为沉淀剂,使铅与硫酸形成硫酸铅沉淀,锌和铜留在溶液中.过滤后,用乙酸-乙酸铵缓冲溶液溶解硫酸铅沉淀,以二甲酚橙为指示剂,EDTA标准溶液滴定铅.分取两份滤液,一份用于测定锌,另一份用于测定铜.测定锌时以氢氧化物沉淀分离铁、锰等金属离子后,在pH5.5乙酸-乙酸钠缓冲液中,硫脲存在下,以二甲酚橙为指示剂,用EDTA标准溶液滴定锌.另一份滤液中铜采用碘化钾-硫代硫酸钠滴定法测定.方法用于铅锌矿样品中铅、锌和铜的测定,测定值与国家标准方法的测定值一致,测定结果的相对标准偏差在0.042％～0.088％之间.
The lead-zinc ore sample was dissolved with hydrochloric acid and nitric acid.Then,the sulfuric acid was added to react with lead ions to form lead sulfate precipitate,while zinc and copper remained in the solution.After filtration,the lead sulfate precipitate was dissolved with acetic acid-ammonium acetate buffer solution.The content of lead was titrated with EDTA standard solution with xylenol orange as indicator.Two parts of filtrate were sampled for the determination of zinc and copper,respectively.During the determination of zinc,iron and manganese ions were firstly precipitated and separated in hydroxide.Then,the content of zinc was determined by titration with EDTA standard solution in acetic acid-sodium acetate buffer solution at pH 5.5 in the presence of thiourea with xylenol orange as indicator.The content of copper in another filtrate was determined by potassium iodide-sodium thiosulfate titration.The proposed method was applied to the determination of lead,zinc and copper in lead-zinc ore samples.The results were consistent with those obtained by national standard method.The relative standard deviations （RSD,n =6） were between 0.042% and 0.088%.
出处
《冶金分析》
CAS
CSCD
北大核心
2014年第12期70-73,共4页
Metallurgical Analysis
关键词
EDTA
硫代硫酸钠
滴定法
铅锌矿
铅
锌
铜
EDTA
sodium thiosulfate
titration
lead-zinc ore
lead
zinc
copper
作者简介
汪更明（1970-）,男,一级实习指导教师,主要从事教学和化学分析的研究工作;E-mail：wgming1@sina.com
