HG-AFS Determination of Arsenic and Mercury in Aluminium Ingot and Aluminium Alloy

The sample of aluminum ingot or alloy was dissolved with HCl-HNO3(3+1),and the contents of arsenic and mercury were determined by HG-AFS.Influential factors,including negative high-voltage,lamp current,the rates of carrier and shield gases,matrix spectrum of aluminium,pH of solution,and concentration of NaBH4 were studied and optimized.The detection limits (3S/N) of arsenic and mercury found were 0.055 and 0.006 2 mg·L-1 ,and values of RSD′s (n=6) were less than 2.5%.The proposed method was applied to the analysis of samples of aluminium ingots and aluminium alloys,and recovery was tested by standard addition method,giving results in the range of 93.3%-103.3 for arsenic and 93.3% -106.7% for mercury.