火焰原子吸收光谱法(FAAS)测定铝基溶液中铁的含量

Determination of Iron in Aluminum-based Solution by FAAS

采用火焰原子吸收光谱法(Flame Atomic Absorption Spectroscopy,FAAS),对铝基溶液中不同含量的铁进行测定.以铝基溶液模拟标样溶解后的溶液,在标准曲线法基础上通过基体匹配或氘灯背景扣除对测试方法进行校正,考察原子吸收对铝基中不同含量的铁测定的可行性,并提高测试准确性.结果表明,在选定的测试条件下,标准曲线法、基体匹配校正和氘灯背景校正的线性相关系数均大于0.999;铝基溶液中铁浓度在4.3μg/mL以上,可以采用火焰原子吸收法进行测定;其中铁浓度在9.40μg/mL以上,可通过氘灯背景校正,提高测试精密度和准确度;铁浓度为4.3μg/mL时可采用基体匹配校正减小基体干扰,保证测试的精密度,同时提高准确性;铁浓度在2.7μg/mL以下,原子吸收法不再适用.使用本研究提供的方法进行校正,RSD值及加标回收率分别在0.51%~2.4%和97%~115.5%范围内,本研究为铝基体系中不同含量铁的准确、快速、高效测定提供了成本低廉、操作性强的实践依据和方法.

Flame atomic absorption spectrophotometry is used to determine iron with different contents in aluminum-matrix solution. Aluminum-matrix solutions are used as testing samples to simulate the aluminum alloy samples. Matrix matching and background deduction correction based on standard method are studied to correct the determination method of iron. The possibility and the policies of accuracy improvement for the FAAS determination of iron with different contents are investigated in this research. The results show that the linear correlation coefficients of the standard curve method, matrix matching correction and the deductive background correction are all greater than 0.999 under the selected test conditions. For the-matrix system, the iron content which is more than 4.3 μg/mL can be determined by flame atomic absorption method. Among them, the Fe content is above 9.40 μg/mL, the precision and accuracy can be improved by deducting background method in the atomic absorption spectrum testing;Fe content is above 4.3 μg/mL, matrix matching method can be used to reduce matrix interference, ensure the precision of the determination and improve the accuracy. When the content of Fe is below2.7 μg/mL, atomic absorption spectrometry is no longer applicable. Using the method provided in this study to calibrate, the RSD and the recovery rate of standard addition are 0.51%~2.4% and 97%~115.5%, respectively.This study provides a low-cost and feasible practice and methodological reference for the accurate, rapid and efficient determination of Fe with different contents in aluminum-matrix samples or solutions.