Aromatic hydrocarbons: including polynuclear

The petroleum-based oils contain hundreds to thousands of hydrocarbon compounds, including a substantial fraction of nitrogen- and sulfur-containing compounds. The hydrocarbons are mainly mixtures of snaight- and branched-chain hydrocarbons (alkanes), cycloalkanes, and aromatic hydrocarbons. Polynuclear aromatic hydrocarbons, alkyl polynuclear aromatic hydrocarbons, and metals are important components of motor oils and crankcase oils, with the used oils... 

The production of coke by the carbonization of bituminous coal leads to the release of chemically complex emissions from coke ovens that include both gases and particulate matter of varying chemical composition. The chemical and physical properties of coke oven emissions vary depending on the constituents. The emissions include coal tar pitch volatiles (e.g., particulate polycyclic organic matter, polycyclic aromatic hydrocarbons, and polynuclear aromatic hydrocarbons), aromatic compounds (e.g., benzene and jS-naphthyl amine), trace metals (e.g., arsenic, beryllium, cadmium, chromium, lead, and nickel), and gases (e.g., nitric oxides and sulfur dioxide). 

Aromatic hydrocarbons (including benzene, Polynuclear aromatic hydrocarbons... 

Methanol use would also reduce pubHc exposure to toxic hydrocarbons associated with gasoline and diesel fuel, including ben2ene, 1,3-butadiene, diesel particulates, and polynuclear aromatic hydrocarbons. Although pubHc formaldehyde exposures might increase from methanol use in garages and tunnels, methanol use is expected to reduce overall pubHc exposure to toxic air contaminants. 

The fused 3+ ring aromatics in petroleum include both cata- and peri-condensed stmctures (see Table 4, Fig. 8). The cata-condensed species are those stmctures where only one face is shared between rings, the peri-condensed molecules are those that share more than one face. The fused ring aromatics form the class of compounds known as polynuclear aromatic hydrocarbons (PAH) which includes a number of recognized carcinogens in the 4+ ring family (33). Because of the potential health and environmental impact of PAH, these compounds have been studied extensively in petroleum. 

Residual fuel oil is generally more complex than distillate fuels in composition and impurities. Limited data are available, but there are indications that the composition of No. 6 fuel oil includes (volume basis) aromatics (25%), paraffins (15%), naphthenes (45%), and nonhydrocarbon compounds (15%). Polynuclear aromatic hydrocarbons and their alkyl derivatives and metals are important hazardous and persistent components of No. 6 fuel oil. 

To determine the concentrations of benzene, toluene, ethylbenzene, and xylenes, approved methods (e.g., EPA SW-846 8021B, SW-846 8260) are not only recommended but are insisted upon for regulatory issues. Polynuclear aromatic hydrocarbons (PAHs) may be present in condensate, and evaluation of condensate contamination should include the use of other test methods (EPA SW-846 8270, SW-846 8310) provided that the detection limits are adequate to the task of soil and groundwater protection. Generally, at least one analysis may be required for the most contaminated sample location from each source area. Condensate releases in nonsensitive areas require analysis for naphthalene only. The analysts should ensure that the method has detection limits that are appropriate for risk determinations. 

After a plate has been exposed to the mobile-phase solvent for the required time, the compounds present can be viewed by several methods. Polynuclear aromatic hydrocarbons, other compounds with conjugated systems, and compounds containing heteroatoms (nitrogen, oxygen, or sulfur) can be viewed with long-and short-wave ultraviolet light. The unaided eye can see other material, or the plates can be developed in iodine. Iodine has an affinity for most petroleum compounds, including the saturated hydrocarbons, and stains the compounds a reddish-brown color. 

A number of different testing kits based on immunoassay technology are available for rapid field determination of certain groups of compounds, such as benzene-toluene-ethylbenzene-xylene (EPA 4030) or polynuclear aromatic hydrocarbons (EPA 4035, Polycyclic Aromatic Hydrocarbons by Immunoassay). The immunoassay screening kits are self-contained portable field kits that include components for sample preparation, instrumentation to read assay results, and immunoassay reagents. 

Chemical/Physical. Incomplete combustion of propane in the presence of excess hydrogen chloride resulted in a high number of different chlorinated compounds including, but not limited to alkanes, alkenes, monoaromatics, alicyclic hydrocarbons, and polynuclear aromatic hydrocarbons. Without hydrogen chloride, 13 nonchlorinated polynuclear aromatic hydrocarbons were formed (Eklund et al, 1987). 

At the Sikes Disposal Pits Superfund site in Crosby, Texas, an HTTS unit was used to treat hazardous organic compounds including phenolic compounds, xylene, benzene, polynuclear aromatic hydrocarbons (PAHs), toluene, creosote, dichloroethane (DCA), vinyl chloride, and naphthalene (D184581, p. 216). The estimated treatment cost was 115 million including approximately 20 million in capital costs and 95 million in operation and maintenance costs. The estimated total cost for thermal treatment was 81 million. A total of 496,000 tons of soil and debris were incinerated. This corresponds to a total unit cost for incineration of 230 per ton and a unit cost of 160 per ton for thermal treatment (D184581, p. 227). 

Solid-phase bioremediation is an ex situ treatment technology for soil and sediment contaminated with total petroleum hydrocarbons (TPH), polynuclear aromatic hydrocarbons (PAHs), and phenols, including pentachlorophenol (PCP). 

Organic contaminants. The concentration of polynuclear aromatic hydrocarbons (PAH) in the particulate phase of flue gases of oil-shale-combusting thermal power plants has been estimated to range from 0.04 to 3.16 mg/m3 (Aunela et al. 1995). The solvent-extractable fraction (<1.5 wt%) from fly ash particles collected from Narva power plant smog chambers included several PAHs (phenanthrene,... 

Photolysis, in the presence of oxygen, of alkenes containing an ally lie hydrogen atom leads to the formation of hydroperoxides. The sensitized process is more efficient, and often yields photoproducts different in structure from those obtained by nonsensitized photooxidation. Cyclohexadiene and related dienes on photolysis in the presence of oxygen yield the transannular peroxides. Thus, on photosensitized oxidation, a-terpinene (410) is converted into ascaridole (411).435 The equivalent process is not, in general, observed in acyclic dienes. Certain polynuclear aromatic hydrocarbons, such as anthracene and naphthacene and including the heterocycles 5,10-diphenyl-1-... 

In the presence of heptakis(6-bromo-6-deoxy-(3-CD) ((3-CD7Br), Femia and Cline Love observed the room-temperature phosphorescence of phenanthrene and other polynuclear aromatic hydrocarbons in N2-purged N,N-dimethylfol-mamide (DMF)-water mixtures [24], On the other hand, Hamai and Monobe observed room-temperature phosphorescence of 2-chloronaphthalene from a deaerated solution containing a 1 1 complex of 6-iodo-6-deoxy-(3-CD ((3-CDI) and 2-chloronaphthalene [25], This result indicates that even only one iodine atom on the (3-CD rim can accelerate the intersystem crossing rate of 2-chloronaphthalene included in the CD cavity. The room-temperature phosphorescence of 6-bromo-2-naphthol and 3-bromoquinoline was also observed for the complexes with (3-CDI [26],... 

There are 14 analytical methods developed by U.S. EPA for measuring common organic pollutants in air. These analytes include aldehydes and ketones, chlorinated pesticides, polynuclear aromatic hydrocarbons, and many volatile organic compounds. These methods may also be applied to analyze other similar substances. All these methods are numbered from TO-1 to TO-14 and based on GC, GC/MS, and HPLC analytical techniques. Method numbers, sampling and analytical techniques, and the types of pollutants are outlined in Table 1, while individual substances are listed in Table 2. 

Similarly, many xenobiotics, such as pesticides, polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), plasticizers, phenols, and some other dmg residues, are also toxic even at trace levels present in the earth s ecosystem [5-7], Without analytical techniques capable of detecting them at nanolevels, we assume the absence of these pollutants in the environment, while these notorious pollutants accumulate in our body tissues resulting in various diseases and side effects such as carcinogenesis and failure of many vital body organs including the kidney, liver, and heart [8-11]. Under such situations, it is essential to have analytical techniques that can detect dmgs, pharmaceuticals, and xenobiotics in biological and environmental samples at very low concentrations. 

Eiceman GA, Clement RE, Karasek FW. 1981. Variations in concentrations of organic compounds including PCDDs and polynuclear aromatic hydrocarbons in fly ash from a municipal incinerator. Anal Chem 53 955-959. 

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