Field screening of petroleum hydrocarbons using synchronous scanning fluorescence spectrometry

摘要

The U.S. Environmental Protection Agency (EPA), National Exposure Research Laboratory (NERL), Characterization Research Division in Las Vegas, Nevada (CRD-LV) is continuing to evaluate the perofrmance of a prototype portable scanning ultravioelt-visible fluorescence instrument as a field scrrening toll. This field ortable scanning spectrofluorometer (FPSS) can rapidly detect the type and relative amount of hydrocarbon contamination in soil and water samples. A recent on site spectrofluorometric analysis of soil and water samples was conducted at an oil refinery in Billings, Montana. Soil and water samples (100 g for soil; 40 mL VOA vial for water) were collected and extracted with iso-ocatane. The extractants were rapidly scanned from 210 nm to 480 nm in the synchronous fluorescence mode. A wavelength offset between the excitation and emission monochromators of 10 nanometers (nm) provided simplified unique spectral fingerprint scans with fluorescence intensity proportional to contaminant concentration. Spectra from environmental samples were compared with site-specific reference standards, including crude oil, fuel oil No. 2 and fuel oil No. 6. The results of the on-site field analyses gave site investigators immediate data that showed the type of hydrocarbon contamination and the relative amounts. Immediate availability of this type of information allows a field investigator to take prompt corrective action as necessary.