光度法测定镀铬液及铬酸钝化液中Cr(Ⅵ)和Cr(Ⅲ)  

Determination of Cr(Ⅵ) and Cr(Ⅲ) in Chromium Plating Bath and Chromic Acid Passivation Bath by Spectrophotometry

作　　者：张东[1] 苏会东[1] 孙德成[2] 安成强[1] 

机构地区：[1]沈阳理工大学环境与化学工程学院,辽宁沈阳110168 [2]沈阳飞机工业(集团)有限公司理化测试中心,辽宁沈阳110034

出　　处：《电镀与精饰》2005年第4期36-38,共3页Plating & Finishing

摘　　要：在硫酸介质中,沸水浴加热条件下,Cr(Ⅵ)能氧化玫瑰桃红R褪色,且褪色程度(ΔA)与Cr( Ⅵ)的质量浓度在一定范围内成正比关系,据此,建立了测定Cr(Ⅵ)和Cr( Ⅲ)的新方法。线性范围为0～8μg/mL,表观摩尔吸光系数为1.7×104L·mol-1·cm-1。该方法可用于镀铬溶液和铬酸钝化液中Cr(Ⅵ)和Cr(Ⅲ)含量的测定。The color fading degree of the oxidative fading reaction of Bordeaux-Red with Cr(Ⅵ) in H_2SO_4medium at 100℃ is in direct proportion to the amount of Cr(Ⅵ) in a certain range, by which a new method for determining Cr(Ⅵ) and Cr(Ⅲ) has been created. The linear range is 0～8 μg/mL for Cr(Ⅵ) . The molar absorptivity is 1.7×10~4 L·mol^(-1)·cm^(-1). The method can be applied to the determination of Cr(Ⅵ) and Cr(Ⅲ) in chromium plating bath and chromic acid passivation bath.

关 键 词：镀铬液 铬酸钝化液 Cr(Ⅵ)和Cr(Ⅲ)?4 玫瑰桃红R 褪色光度法 

分 类 号：TQ115.335[化学工程—无机化工]