焦磷酸盐铜-镍合金镀液中硫酸镍的分析  

Analysis of Nickel Sulfate in Pyrophosphate Copper-nickel Alloy Plating Bath

作　　者：黎小阳 郭崇武[1] 

机构地区：[1]广州超邦化工有限公司,广东广州510460

出　　处：《电镀与精饰》2016年第6期36-38,共3页Plating & Finishing

摘　　要：制定了测定焦磷酸盐铜-镍合金镀液中硫酸镍的返滴定法。在加热条件下用硫酸分解焦磷酸,使其转变为磷酸。用抗坏血酸和硫脲掩蔽镀液中的铜离子和铁杂质,在pH=5.4的条件下,加入过量的EDTA标准滴定溶液配合镍离子,以二甲酚橙作指示剂,用硫酸锌标准滴定溶液返滴定EDTA,从而得到硫酸镍的质量浓度。试验表明,本法的相对平均偏差为0.22%,回收率为99.68%。用返滴定法解决了镍离子对二甲酚橙指示剂的封闭问题。A back titration method for measuring the nickel sulfate in pyrophosphate copper-nickel alloy plating bath was established. Pyrophosphoric acid was decomposed to form phosphoric acid by using sulfuric acid under heating condition. Copper ions and iron impurities in the plating bath were masked by using ascorbic acid and thiourea; excess EDTA standard titration solution was added under pH = 5. 4 condition to complex the nickel ions; Re-titration measurement of EDTA was carried out by zinc sulfate standard solution with xylenol orange as the indicator,thereby the nickel sulfate mass concentration was obtained. Experimental results showed that the relative average deviation of this method was 0. 22% and the recovery percentage was 99. 68%. Blocking problem of the nickel ions to xylenol orange indicator was resolved by this back titration method.

关 键 词：焦磷酸盐 铜-镍合金镀液 焦磷酸 正磷酸 硫酸镍 返滴定 掩蔽剂 二甲酚橙指示剂 

分 类 号：TQ153.2[化学工程—电化学工业]