流动注射标准加入双波长光度法同时测定铁和铝

SIMULTANEOUS DETERMINATION OF IRON AND ALUMINIUM WITH FLOW INJECTION-STANDARD ADDITION DUAL WAVELENGTH SPECTROPHOTOMETRY

研究了用流动注射分析(FIA)进行双波长标准加入法同时测定铁和铝的新方法.方法基于在溴化十六烷基三甲胺存在下,络天青S与铁和铝在同一酸度(pH 6.75)均有灵敏的显色反应,但两配合物的吸收光谱互相重叠.在优化的试验条件下,铁和铝检出限分别为0.001和0.002μg·ml^(-1),铁浓度在0～1.2μg·ml^(-1)、铝浓度在0～0.8μg·ml^(-1)时服从比耳定律,测样频率为60样·h^(-1),所拟方法用于实际样品分析,结果良好.

It is reported in this paper that the hyphenation of FIA technique and DW-spec-trophotometry is applied to the simultaneous determination of iron and aluminum with CAS as chromogenic reagent in the presence of CTMAB. The chromogenic reaction is carried out in an NH_(4)OAc buffer solution of pH 6. 75. Under optimum conditions, the detection limits are 0. 001/礸 ?ml^(-1) for iron and 0. 002礸 ?ml_(-1) for aluminum, and Beer's law is obeyed in the ranges of 0~ 1. 2礸 ?m_(-1) for iron and 0~0. 8/礸 ?ml_(-1) for aluminum. The sampling rate of the FIA system is 60 samples per hour. The proposed method has been applied to the determination of iron and aluminumin copper alloys with satisfactory results.