Petroleum hydrocarbon content

Total Organic Carbon Formations with a significant TOC content greater than the petroleum hydrocarbon content, as with peat-rich soil, can compete with the hydrocarbon-degrading microbes for oxygen and nutrients. A representative sample should thus be analyzed for TOC if organic matter is observed in soil samples or borings. 

Large-scale SCP production processes for growing yeasts of the genus Candida from hydrocarbon substrates were developed by British Petroleum Co., Ltd. and Kanegafuchi Chemical Industry, Ltd. of Japan (57). However, the 100,000-t/yr capacity plants based on these processes, and constmcted in Sardinia and Italy, were abandoned because of regulatory agency questions regarding residual hydrocarbon contents of the products (2,3). 

Chemical characteristics of importance to natural attenuation processes include petroleum hydrocarbon or organic compound type, concentration, pH, and nitrogen and phosphorus content. 

Among the polynuclear aromatic hydrocarbons, the toxicity of petroleum is a function of its di- and triaromatic hydrocarbon content. Like the single aromatic... 

Therefore, methods for the analysis of total petroleum hydrocarbon are frequently used to find areas of gross contamination but are often inadequate even for this task. Indeed, any one of several variables, such as differences in moisture content, can lead to analytical inconsistencies, and therefore the data do not consistently give reliable insights as to which part of the site is most contaminated. 

It is possible that the photoionization detector (1) may not be completely selective for aromatics and can lead to an overestimate of the more mobile and toxic aromatic content and (2) the results from the two analyses, purge-able and extractable hydrocarbons, can overlap in carbon number and cannot simply be added together to get a total concentration of the total petroleum hydrocarbons. 

An alternative method for fractionating and purifying petroleum hydrocarbons prior to GC or HPLC separation has been developed (Theobald 1988). The method uses small, prepacked, silica or Cjg columns that offer the advantage of rapid separation (approximately 15 minutes for a run) good recovery of hydrocarbons (85% for the Cjg column and 92% for the silica column) reusability of the columns and for the silica column in particular, good separation of hydrocarbon from non-hydrocarbon matrices as may occur with environmental samples. Infrared analysis and ultraviolet spectroscopy were used to analyze the aromatic content in diesel fuels these methods are relatively inexpensive and faster than other available methods, such as mass spectrometry, supercritical fluid chromotography, and nuclear magnetic resonance (Bailey and Kohl 1991). 

The Biolysis process is an aerobic bioremediation treatment designed to treat soils and sludges with a high solids content contaminated with petroleum hydrocarbons and nonsoluble organics. It... 

Initial total PAH concentration 1.4g/kg Total petroleum hydrocarbons 5.7-7.0g/kg Sandy loam Organic carbon content 1.8% Soil moisture 80% of WHC Solid phase organic amendment Seech et al. (1994)... 

In the studies carried out to date, eight fuels have been tested which include six synfuels and two petroleum derived fuels. The synfuels tested included SRC-II middle and heavy distillate fuels, a blend of these fuels, and one SRC fuel blended with the process donor solvent. Composition data for the various fuels are presented in Table I, where it can be seen that the coal derived liquids have a higher C H ratio than either the diesel or residual petroleum oils, indicative of a higher aromatic hydrocarbon content. The shale-derived DFM on the other hand is a highly processed fuel and has a C H ratio similar to the petroleum diesel oil. Complete analyses of all the actual fuels tested were unfortunately not available at the time of writing, and, where necessary, typical analyses have been taken from previous studies. 

Pearson, A., Kraunz, K. S., Sessions, A. L., Dekas, A. E., Leavitt, W. D., and Edwards, K. J. (2008). Quantifying microbial utilization of marsh sediments by using the C-13 petroleum hydrocarbons in salt content of bacterial rRNA . Appl. Environ. Microbiol. 74, 1157—1166. 

Many methods are available for analysis of petroleum hydrocarbon products, particularly in water and soil matrices. The current literature includes a number of studies that document the performance and limitations of the commonly used methods. Method modifications and new methods are being investigated to provide better information about the petroleum component content of environmental samples. However, the available analytical methodology alone may not provide adequate information for those who evaluate the movement of petroleum components in the environment or evaluate the health risks posed to humans (Heath et al. 1993a). 

The content of this chapter and this document is different from that of a standard toxicological profile, in recognition of the extensive assessments of individual petroleum hydrocarbons already performed by ATSDR and other agencies, and the need for an approach that focuses on the most important information. This chapter presents the ATSDR perspective and approach, and serves as a guide to sources of more detailed information. 

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