化学学报 ›› 1965, Vol. 31 ›› Issue (5): 391-398. 上一篇    下一篇

论文

隐蔽剂在螯合滴定中的应用——Ⅱ.以乳酸隐蔽钛(Ⅳ)与钛的间接滴定

陈永兆, 李煥然   

  1. 中山大学化学系
  • 投稿日期:1964-10-04 发布日期:2013-06-03

THE USES OF MASKING AGENTS IN CHELOMETRY Ⅱ. THE MASKING OF TITANIUM(Ⅳ) WITH LACTIC ACID AND THE INDIRECT TITRATION OF TITANIUM

CHEN YUNG-CHAO, LI HUAN-JAN   

  1. Chemistry Department, Sun Yat-Sen University
  • Received:1964-10-04 Published:2013-06-03

本文确定乳酸不失为酸性溶液中一良好隐蔽剂,在pH5—6间,能隐蔽大量钛(Ⅳ)。在pH 5.3,10毫升1:4乳酸能隐蔽70毫克的钛,使滴定不为乳酸隐蔽的离子如铁、锆、铝、铅等不受钛的干扰。乳酸能嚣换络合钛(Ⅳ)的EDTA,使在不为乳酸隐蔽的十种元素存在下(铁、锆、铝、铋、锌、镉、铅、铜、钴和镍)能选择滴定钛,可能用于测定钛铁矿、钛合金与钛化合物等快速而又准确测定钛的新方法。在pH2.5间将钛(Ⅳ)-EDTA络合物煮沸一刻钟以上,能使钛(Ⅳ)与EDTA络合完全,继调至pH5—6后钛不水解,而能定量滴定,此点已用于以乳酸置换法准确间接滴定钛。

It is found experimentally that lactic acid is a good masking agent for titanium (Ⅳ) in acidic media. At pH 5.3 and 5.8,10ml of 1:4 (V/V) lactic acid masks up to 70 and 40 mg of titanium respectively. Those ions, such as iron (Ⅲ),aluminum, lead, etc., which are not masked by lactic acid, can be titrated without the interference of titanium.