Total recoverable petroleum hydrocarbons

There is one case in environmental work where the methyl and methylene absorptions are useful and used. This is in the United States Environmental Protection Agency (USEPA) method for the determination of total recoverable petroleum hydrocarbons (TRPHs) in a soil or other extract. Here, a supercritical carbon dioxide extraction of a hydrocarbon-contaminated soil is made (EPA Method 3560). The extracted hydrocarbons are dissolved in... 

Supercritical fluid extraction (EPA 3540, for total recoverable petroleum hydrocarbons EPA 3561 for polynuclear aromatic hydrocarbons) is applicable to the extraction of semivolatile constituents. Supercritical fluid extraction involves heating and pressuring a mobile phase to supercritical conditions (where the solvent has the properties of a gas and a liquid). The supercritical fluid is passed through the soil sample, and the analytes are concentrated on a sorbent or trapped cryogenically. The analytes are eluted with a solvent and analyzed using conventional techniques. Carbon dioxide is the most popular mobile phase. 

Supercritical fluid extraction of total recoverable petroleum hydrocarbons (TRPH)... 

Freon-extractable material is reported as total organic material from which polar components may be removed by treatment with silica gel, and the material remaining, as determined by infrared (IR) spectrometry, is defined as total recoverable petroleum hydrocarbons (TRPHs, or total petroleum hydrocarbons-IR). A number of modifications of these methods exist, but one particular method (EPA 418.1 see also EPA 8000 and 8100) has been one of the most widely used for the determination of total petroleum hydrocarbons in soils. Many states use or permit the use of this method (EPA 418.1) for identification of petroleum products and during remediation of sites. This method is subject to limitations, such as interlaboratory variations and inherent inaccuracies. In addition, methods that use Preon-113 as the extraction solvent are being phased out and the method is being replaced by a more recent method (EPA 1664) in which n-hexane is used as the solvent and the n-hexane extractable material (HEM) is treated with silica gel to yield the total petroleum hydrocarbons. 

Like total petroleum hydrocarbons, total recoverable petroleum hydrocarbons (TRPH) is defined methodologically and concentrations given as total petroleum hydrocarbons, or TRPH alone, does not produce much valuable information. To be able to understand the significance of the concentration, the method employed... 

Total recoverable petroleum hydrocarbons EPA 1664 EPA 418.1 SM 5520 (F) One liter amber glass, PTFE-lined lid 1000 ml 2 to 6°C, HC1 pH <2 28 days for extraction, 40 days for analysis ... 

Total Recoverable Petroleum Hydrocarbons Volatile PAHs Less Volatile PAHs Organochlorine Pesticides PCBs... 

IR = infrared spectrophotometry MS = mass spectrometry MSD = mass selective detector SIM = selected ion monitoring TPH = total petroleum hydrocarbons TRPH = total recoverable petroleum hydrocarbons... 

EPA method 3560, Supercritical Fluid Extraction of Total Recoverable Petroleum Hydrocarbons, Test Methods for Evaluating Solid Waste, EPA, Washington D.C., 1996. 

EPA Method 3560, Supercritical Fluid Extraction of Total Recoverable Petroleum Hydrocarbons, 1996. 

EPA. 1979c. Methods for chemical analysis of water and wastes Method 418.1 (spectrophotometric, infrared) petroleum hydrocarbons, total recoverable. U.S. Environmental Protection Agency, EPA-600-79-020. 

The definitions above are an abbreviated version of those used in a veiy complex and financially significant exercise with the ultimate goal of estimating resei ves and generating production forecasts in the petroleum industry. Deterministic estimates are derived largely from pore volume calculations to determine volumes of either oil nr gas in-place (OIP, GIP). This volume when multiplied by a recovery factor gives a recoverable quantity of oil or natural gas liquids—commonly oil in standard barrels or natural gas in standard cubic feet at surface conditions. Many prefer to use barrels of oil equivalency (BOE) or total hydrocarbons tor the sum of natural gas, natural gas liquids (NGL), and oil. For comparison purposes 6,000 cubic feet of gas is considered to be equivalent to one standard barrel on a British thermal unit (Btu) basis (42 U.S. gallons). 

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