自动电位滴定法测定氯化钾镀锌溶液的硼酸  

Determination of boric acid in potassium chloride-based zinc electroplating bath by automatic potentiometric titration

作　　者：王晓红 王琳[1] 韩卫平[1] 程星华[1] 刘涛[1] 喻晓军[1] WANG Xiaohong;WANG Lin;HAN Weiping;CHENG Xinghua;LIU Tao;YU Xiaojun(Advanced Technology and Materials Co.,Ltd.,Beijing 101318,China)

机构地区：[1]安泰科技股份有限公司,北京101318

出　　处：《电镀与涂饰》2022年第23期1717-1721,共5页Electroplating & Finishing

基　　金：国家重点研发计划资助(2021YFB3503004)。

摘　　要：建立了氯化钾镀锌溶液中硼酸含量的自动电位滴定方法。以草酸钾掩蔽锌离子和铁离子,用甘露醇将硼酸转化为强酸,以非水相pH复合电极作为指示电极,用氢氧化钠标准溶液进行滴定。实验考察了指示电极种类、掩蔽剂种类、掩蔽剂加入量、甘露醇加入量、反应时间等对测定结果的影响,确定了最佳测定条件。分析结果的相对标准偏差为0.3%~0.5%(n=6)。该法准确可靠,测量过程简便快速,可以满足日常电镀生产过程中硼酸含量快速检测的要求。A method for automatic potentiometric titration of boric acid in potassium chloride-based zinc electroplating bath was established.The zinc and iron ions are masked by potassium oxalate.The boric acid is converted to a strong acid by reaction with mannitol.A combined pH electrode for nonaqueous titration was used as the indicator electrode,and a sodium hydroxide standard solution as the titrant.The effects of several factors i.e.the type of indicator electrode,the type and dosage of masking agent,the dosage of mannitol,and reaction time on the determination results were studied,and the optimal titration conditions were determined.The relative standard deviation of the analysis results is 0.3%-0.5%(n=6).The method is simple and fast with high accuracy and reliability,meeting the requirements of rapid detection during routine electroplating production process.

关 键 词：氯化钾镀锌液 硼酸 自动电位滴定 草酸钾 甘露醇 氢氧化钠 

分 类 号：O655[理学—分析化学]