Determination of Chalorine Concentration in Atmospheric Particles by X-Ray Absorption Near Edge Spectrometry

Abstract

An analytical method of X-ray absorption near edge spectrometry(1sXANES) including the quality control for chlorine species in the atmospheric particles was established.The inorganic and aromatic and aliphatic chlorine in the standard and ≤0.2 atmospheric particle samples were analyzed under the conditions of 300-350 synchrotron radiation light beam intensity,storage ring energy of 1.5 GeV and photon energy of 2.82 keV.Calculated by fitting standard spectra,the method detection limits of inorganic,aliphatic and aromatic chlorine were 5.4,8.7 and 1.7 μg/g,respectively.The detectable frequency of atmospheric particle samples was almost 95%.The relative standard deviation(RSD) of repeated measurements of 3-chloro acid standard was 0.9%(n=6).The method was successfully applied to analyze the urban atmospheric particles non-destructively.The contents of inorganic chlorine,aromatic hydrocarbon-substituded organic chlorine in atmospheric ultra-fine particles(≤0.2 μm) were 110 and 12 ng/m3,respectively,while the chain hydrocarbon substituted organic chlorine was not detected.The developed method was applied to the determination of chlorine species concentration in the atmospheric particles.The results showed that the main chlorine species in one place of Beijing were inorganic chlorine and aromatic chlorine.