Aromatic hydrocarbon

About: Aromatic hydrocarbon is a research topic. Over the lifetime, 5814 publications have been published within this topic receiving 55499 citations. The topic is also known as: arene & arenes.

Coupling transport and biodegradation of VOCs in surface and subsurface soils.

Abstract: Volatile organic chemicals present at Superfund sites preferentially partition into the soil gas and may be available for microbial degradation. A simple mass transfer model for biodegradation for volatile substrates has been developed for the aerobic decomposition of aromatic and aliphatic hydrocarbons. The mass transfer analysis calculates diffusive fluxes from soil gas through water and membrane films and into the cell. This model predicts an extreme sensitivity of potential biodegradation rates to the air-water partition coefficients of the compounds. Aromatic hydrocarbons are removed rapidly while the aliphatic hydrocarbons are much slower by orders of magnitude. Furthermore, oxygen transfer is likely to limit aromatic hydrocarbon degradation rates. The model presents results that cast doubt on the practicality of using methane or propane for the co-metabolic destruction of trichloroethylene in a gas phase bioreactor. Toluene as a primary substrate has better mass transfer characteristics to achieve more efficient trichloroethylene degradation. Hence, in sites where these contaminants coexist, bioremediation could be improved.

Change in the Predominant Bacteria in a Microbial Consortium Cultured on Media Containing Aromatic and Saturated Hydrocarbons as the Sole Carbon Source

Abstract: A No.22 consortium was isolated from contaminated soils at oilfields by repeated transfer on a mineral salts medium with the aromatic hydrocarbon fraction from crude petroleum. The consortium was able to degrade aromatic hydrocarbons at high rates. Fourteen major DNA bands were detected in the consortium by PCR-DGGE. Three strains were capable of forming colonies on agarose plates containing mineral salts and aromatic hydrocarbons, and identified as Pandoraea sp. Y1, Hyphomicrobium facile Y3, and Burkholderia multivorans Y4 by 16S rRNA gene sequencing. The consortia of three cultures; an aromatic subculture, a saturated culture transferred from the subculture, and an aromatic obtained culture from the transferred culture, were compared using PCR-DGGE, a clone library, and quantitative real-time PCR. Burkholderia species containing strain Y4 became the dominant species in the saturated culture whereas its abundance decreased in the aromatic culture. Pandoraea sp. Y1, which was of low abundance in the saturated culture, and an unisolated bacterium, Brachymonas sp. F, in contrast, increased in the aromatic culture. The aromatic hydrocarbons were degraded by Pandoraea sp. Y1 and B. multivorans Y4, whereas the saturates were only degraded by B. multivorans Y4. The results indicate that the No.22 consortium adapts well to different carbon sources through a change in its predominant species. This study provides some basic information regarding bioremediation using the consortium.

Method of analyzing diesel oil hydrocarbon composition using solid phase extraction and mass chromatogrophy

Abstract: The method for analyzing diesel hydrocarbon composition by using solid phase extraction and mass spectrography includes the following steps: using solid phase extraction process to separate saturated hydrocarbon and aromatic hydrocarbon in diesel sample, collecting all the saturated hydrocarbon solution and aromatic hydrocarbon solution, respectively adding equivalent internal standard material, then respectively sampling and making gas chromatography and mass spectrography; utilizing gas chromatomap of aromatic hydrocarbon and saturated hydrocarbon to calculate relative content of both them, and utilizing mass spectrogram to obtain hydrocarbon composition of aromatic hydrocarbon and saturated hydrocarbon; according to the relative content of saturated hydrocarbon and aromatic hydrocarbon using normalization-calculation method to obtain the hydrocarbon composition of diesel.