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Abstract: An ultrasound-enhanced elution system with Triton X-100 solution was used to remediate aging soils contaminated with super heavy oil. We used GC/MS, SEM, and X-ray diffraction (XRD) to analyze the effect of ultrasonic time (0–1800s) on the elution of super heavy oil and its three characteristic biomarkers (C26–34 17α 25-norhopanes, C26–28 triaromatic steroid [TAS], and C27–29 methyl triaromatic steroid [MTAS]). The oil and biomarkers remaining in the treated soils followed similar second-order functions with increasing ultrasonication times. Biomarker elution was closely related to carbon numbers in the marker. For C26–34 17α 25-norhopanes, the smaller molecules were more readily eluted during 0–360s ultrasound. This trend was reversed upon application of ultrasound during 1080–1800s, with improved elution of larger molecules and elution followed a similar second-order function. For C26–28 TAS, smaller molecules were more readily eluted but the elution of larger molecules followed a similar second-order function. For C27–29 MTAS, elution of larger molecules was close to that of C26–34 17α 25-norhopanes. Results of SEM and XRD indicated that the mineral and chemical compositions of soils eluted at ultrasonication times of 1080–1800s closely resembled clean soils. [Copyright &y& Elsevier]

Abstract: An ultrasound-enhanced elution system employing Triton X-100 solutions was used for remedying aging soils contaminated with super heavy oil. The effect of varying the ultrasonic power density on the elution of the oil and three characteristic biomarkers was analyzed using GC/MS and FTRS. The oil and biomarkers remaining in treated soils decreased as a similar first-order function of increasing ultrasonic power density. Elution of the three biomarkers in the absence of ultrasound was closely related to carbon numbers in the marker: smaller molecules were more readily eluted. This trend was reversed upon application of ultrasound at higher power densities, with improved elution of molecules containing a greater carbon numbers. The two ratios, both 22S/(22S +22R) of C26–34 17α 25-norhopanes and 20S/(20S +20R) of C26–28 triaromatic steroids, in treated soils decreased with increasing power density from 20 to 100WL−1. The results of SEM, FTRS, XRD, and energy spectroscopy experiments indicated that the mineral and chemical compositions of soils eluted at power densities greater than 60WL−1 closely resembled clean soils. [Copyright &y& Elsevier]