Fiber optic spectrochemical emission sensor: Detection of volatile chlorinated compounds in air and water using ultra-thin membranes.

摘要

Prior work on the fiber optic spectrochemical emission sensor called HaloSnif(trademark) has been extended to include an ultra-thin membrane which allows passage of volatile organic chlorinated compounds (VOCl). The membrane has been demonstrated to exclude H(sub 2)O during VOCl monitoring. The system is capable of measuring VOCl in gas-phase samples or aqueous solutions over a wide linear dynamic range. The lower limit of detection for trichloroethylene (TCE), perchloroethylene (PCE), carbon tetrachloride (CCl(sub 4)), and other related compounds in the gas-phase is 1 to 5 ppm(sub v/v), and in the aqueous-phase is 5 to 10 mg/L. Waste site characterization and remediation activities often require chemical analysis in the vadose zone and in groundwater. These analyses are typically performed in analytical laboratories using widely accepted standardized methods such as gas chromatography, gas chromatography/mass spectrometry. The new developments with HaloSnif provide rapid field screening which can augment the standardized methods.