火焰原子吸收光谱法测定铜-钛改性的碳/碳-碳化硅复合材料中高含量铜

Determination of high content copper in carbon/carbonsilicon carbide composites modified with copper-titanium by flame atomic absorption spectrometry

铜-钛改性的碳/碳-碳化硅(C/C-SiC)复合材料的主要成分为铜钛碳硅,不易被常规方法溶解。采用在800~820℃先将样品灼烧20min以消除碳的干扰,再从瓷坩埚转于刚玉坩埚中碱熔,并加入盐酸和硝酸进一步溶解样品,建立了以2.0%盐酸为测定溶液介质、火焰原子吸收光谱法测定铜-钛改性的C/C-SiC复合材料中铜的方法。研究表明,铜浓度在2~12μg/mL范围内与吸光度呈良好的线性关系,线性回归方程为y=0.015 31+0.059 66x,线性相关系数R=0.999 4,方法检出限为0.011 2μg/mL。采用方法对铜-钛改性的C/C-SiC复合材料自制样品FL-2和内控样品C6分别进行测定,结果与参考值或碘量法基本一致,相对标准偏差(RSD,n=6或12)分别为0.39%和1.1%。

The main components of carbon/carbon-silicon carbide(C/C-SiC)composites modified with copper-titanium were copper,titanium,carbon and silicon,and it was insoluble by conventional method.The sample was firstly burned at 800-820℃for 20 min to eliminate the interference of carbon,then transferred from ceramic crucible to corundum crucible for alkali fusion,and at last further dissolved by hydrofluoric acid and nitric acid.Based on this,a method for the determination of copper in C/C-SiC composites modified with copper-titanium was established by flame atomic absorption spectrometry with the test medium as 2.0%hydrofluoric acid.It showed that,the concentration of copper kept a fine linear relationship with the absorbance within the range of 2-12μg/mL with the linear regression equation of y=0.015 31+0.059 66 xand linear correlation coefficient of R=0.999 4.The detection limit was 0.011 2μg/mL.The self-made sample FL-2and internal control sample C6 of C/CSiC composites modified with copper-titanium were determined by the proposed method respectively.The results were consistent with the reference values or that by iodometry,and the relative standard deviation(RSD,n=6or 12)was 0.39%and 1.1%respectively.