BCO光度法测定氨氰体系溶液中铜氨络离子态铜量

摘要

本次工作建立了氨氰体系溶液中铜氨络离子态铜量的BCO测定方法，解决了多价态铜离子络合物体系溶液中铜氨离子的选择性测定问题。在pH值为9.0的氨水-氯化铵缓冲溶液中，用柠檬酸铵溶液掩蔽其他的金属离子，采用分光光度法测定氨氰体系溶液中铜氨络离子态铜（Ⅱ）的含量。铜氨络离子态铜（Ⅱ）与BCO形成蓝色络合物，其最大吸收波长位于600 nm，线性相关系数达0.9999，检出限为0.010 mg/L。对氨氰体系溶液进行加标回收，加标回收率为97%~102%，相对标准偏差（n=6）在0.09%~0.46%之间。该方法不经过复杂的处理步骤，操作便捷、测定迅速且准确可靠。%BCO determination method of copper ammonia complex ion in ammonia cyanide solution was established to solve the problem of determine copper ammonia complex ion content in multi-valence copper ion complex solution.Ammonium citrate solution was used to mask other metal ions in the ammonia-ammonium chloride buffer solution(pH=9.0) and the Cu(Ⅱ) content was determined by BCO photometric method in the ammonia solution cyanide system as copper ammonia complex ion.Cu(Ⅱ) in copper ammonia complex ion reacted with BCO to form blue complex,which has a maximum absorption wavelength of 600 nm,with a linear correlation coefficient of 0.9999 and a detection limit of 0.010 mg/L.The recovery rate of adding standard was 97% to 102%, and the relative standard deviation (n=6)was 0.09% to 0.46%.The method does not require complex processing steps and has the advantages of simple, rapid, accurate, reliable and easy operation.