镀镍溶液中硼酸的分析方法

Analysis Method of Boric Acid in a Nickel Plating Bath

制定了测定镀镍溶液中硼酸的新方法。用草酸钾掩蔽镀液中的镍离子和镀液中铁杂质及锌杂质离子,用氟化钠掩蔽铝杂质离子,用甘露醇与硼酸反应生成酸性较强的配合酸,用酚酞作指示剂,以氢氧化钠滴定法测定配合酸。实验表明,本法的相对平均偏差为0.2%,回收率为99.62%,精密度和回收率都较高。

A novel method of measuring boric acid in a nickel plating bath was established. The nickel ion,iron impurity,and zinc impurity in the plating bath were masked by potassium oxalate. The aluminum impurity was masked using sodium fluoride. The boric acid reacted with D-mannitol to produce a stronger complex acid which had stronger acidity than boric acid. The complex acid was titrated by utilizing sodium hydroxide standard titrating solution with phenothalin as indicator. The experiments showed that the relative average deviation of analysis results was 0. 2% and the percent recovery was 99. 62%.