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Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy(LIBS). A pulsed neodymium-doped yttrium aluminum garnet(Nd:YAG) laser(1,064 nm, 8 ns, 200 mJ) was focused onto pelletized soil samples. Emission spectra were obtained from oil-contaminated soil and clean soil. The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C–H molecular band was clearly detected in the oil-contaminated soil, while no C–H band was detected in the clean soil. Linear calibration curve of the C–H molecular band was successfully made by using a soil sample containing various concentrations of oil. The limit of detection of the C–H band in the soil sample was 0.001 mL/g. Furthermore, the emission spectrum of the contaminated soil clearly displayed titanium(Ti) lines, which were not detected in the clean soil. The existence of the C–H band and Ti lines in oil-contaminated soil can be used to clearly distinguish contaminated soil from clean soil. For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray(SEM/EDX) spectroscopy,showing that the spectra obtained using LIBS are much better than using SEM/EDX, as indicated by the signal to noise ratio(S/N ratio).
Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy (LIBS). A pulsed neodymium-doped yttrium aluminum garnet (Nd: YAG) laser (1,064 nm, 8 ns, 200 mJ) was focused onto pelletized soil samples The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C-H molecular band was clearly detected in the oil -contaminated soil, while no C-H band was detected in the clean soil. Linear calibration curve of the C-H molecular band was successfully made using a soil sample containing various concentrations of oil. The limit of detection of the C-H band in the soil sample was 0.001 mL / g. The emission spectrum of the contaminated soil clearly displayed titanium (Ti) lines, which were not detected in the clean soil. The existence of the C-H band and Ti lines in oil -contaminated soil can For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray (SEM / EDX) spectroscopy, showing that the spectra obtained using LIBS are much better than using SEM / EDX, as indicated by the signal to noise ratio (S / N ratio).