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Abstract: We examined the effects of power and treatment time on the ultrasonically enhanced ozonation of carbazole dissolved in APG1214 surfactant solutions, including an analysis of the mechanism of l formation, the zeta potential of the colloidal suspension, the influence of ultrasound on micellar morphology, and the degradation kinetics for carbazole and APG1214. A 30min ultrasound treatment at 28kHz and 20W improved the degradation of carbazole by 5–10%, while power levels of 40W and 80W provided improvements only during the first 5min and resulted in reduced degradation after 15min. The tration was inversely proportional to ultrasound power, and directly proportional to the irradiation time. The absolute value of the APG1214 micelle zeta potential was inversely proportional to power and decreased with increasing irradiation time. The relationships of l concentration in APG1214 micelles, the zeta potential, and the micellar dynamic radius (R h) to ultrasonic power and time are the key factors affecting carbazole degradation in this system. [Copyright &y& Elsevier]

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 water at a temperature of 70°C was used to remedy weathered soils contaminated with severely biodegraded heavy oil (SBHO). The effect of varying the ultrasonic irradiation time from 0 to 1800s on the elution of SBHO and three characteristic biomarkers (C26–34 17α 25-norhopanes, C26–28 TAS, and C27–29 MTAS) was analyzed using GC/MS, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Elution of the three biomarkers was closely related to the carbon number of the marker. C26–34 17α 25-norhopanes and C26–28 TAS species with higher carbon numbers and C27–29 MTAS species with lower carbon numbers were more readily eluted using sonication times of 1080–1800s, while smaller TAS homologs were more readily eluted after sonication times of 0–360s. SEM images of samples treated for longer periods revealed larger “bare patches” on the soil surface. The results of XRD and energy spectroscopy experiments indicated that ultrasound irradiation for 1080s negatively affected the deposition of CaCO3, but overall improved the mineral and chemical compositions of treated soils and removal of SBHO. [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]

The adsorption of organic pollutants from super heavy oil wastewater (SHOW) by lignite activated coke (LAC) was investigated. Specifically, the effects of LAC adsorption on pH, BOD 5 /COD Cr (B/C), and the main pollutants before and after adsorption were examined. The removed organic pollutants were characterized by Fourier transform infrared spectroscopy (FTIR), Boehm titrations, gas chromatography–mass spectrometry (GC–MS), and liquid chromatography with organic carbon detection (LC–OCD). FTIR spectra indicated that organic pollutants containing COOH and NH 2 functional groups were adsorbed from the SHOW. Boehm titrations further demonstrated that carboxyl, phenolic hydroxyl, and lactonic groups on the surface of the LAC increased. GC–MS showed that the removed main organic compounds are difficult to be degraded or extremely toxics to aquatic organisms. According to the results of LC–OCD, 30.37 mg/L of dissolved organic carbons were removed by LAC adsorption. Among these, hydrophobic organic contaminants accounted for 25.03 mg/L. Furthermore, LAC adsorption was found to increase pH and B/C ratio of the SHOW. The mechanisms of adsorption were found to involve between the hydrogen bonding and the functional groups of carboxylic, phenolic, and lactonic on the LAC surface. In summary, all these results demonstrated that LAC adsorption can remove bio-refractory DOCs, which is beneficial for biodegradation. [ABSTRACT FROM AUTHOR]

The widely applied aromatic nitration in modern industry leads to toxic p -nitrophenol (PNP) in environment. Exploring its efficient degradation routes is of great interests. In this study, a novel four-step sequential modification procedure was developed to increase the specific surface area, functional group, hydrophilicity, and conductivity of carbon felt (CF). The implementation of the modified CF promoted reductive PNP biodegradation, attaining 95.2 ± 0.8% of removal efficiency with less accumulation of highly toxic organic intermediates (e.g., p -aminophenol), compared to carrier-free and CF-packed biosystems. The constructed anaerobic-aerobic process with modified CF in 219-d continuous operation achieved further removal of carbon and nitrogen containing intermediates and partial mineralization of PNP. The modified CF promoted the secretion of extracellular polymeric substances (EPS) and cytochrome c (Cyt c), which were essential components to facilitate direct interspecies electron transfer (DIET). Synergistic relationship was deduced that glucose was converted into volatile fatty acids by fermenters (e.g., Longilinea and Syntrophobacter), which donated electrons to the PNP degraders (e.g., Bacteroidetes_vadinHA17) through DIET channels (CF, Cyt c, EPS) to complete PNP removal. This study proposes a novel strategy using engineered conductive material to enhance the DIET process for efficient and sustainable PNP bioremediation. [Display omitted] • Four-step sequential modification for carbon felt (CF) was conducted. • Modified CF promoted PNP biodegradation, with less accumulation of PAP. • DIET was enhanced between fermenters and PNP degraders. • Contents of EPS and Cyt c facilitating DIET increased. [ABSTRACT FROM AUTHOR]