FL-XANES The Design of Anoxic Air Sample Preservation and Study of Sulfur Speciation of PM10 in the Atmosphere by Using FL-XANES (Fluorescent Mode X-ray Absorption Near Edge Structure)

Abstract

This paper focuses on providing some innovative perspectives related to the factors affecting the sulfur K-edge XANES spectrum of aerosol samples. Anoxic Preservation Stainless Cylinder (APSC) and Pressure Controlled Glove Box (PCGB) were specially designed for investigating the anoxic preservation effect on variations of sulfur oxidation states in PM10. Further investigation on sulfur K-edge XANES spectra revealed that PM10 samples were predominantly dominated by S(VI) even though preserved in anoxic conditions. The “emission source” effect on sulfur oxidation state of PM10 was examined by comparing sulfur K-edge XANES spectrum collected from various emission sources in Songkla Province, southern part of Thailand. Additional attempt was conducted on an investigation of “vertical distribution” effects on sulfur oxidation state of PM10 collected from three different heights at the highest buildings of three major cities in Thailand. The analytical results have demonstrated that neither “emission sources” nor “vertical distribution” effects appreciably contribute to the variations of sulfur K-edge XANES spectrum in PM10.