Polynuclear aromatic hydrocarbon compounds

Oyler, A.R., Llukkonen, R.J., Lukasewycz, M.T., Heikkila, K.E., Cox, D.A., and Carlson, R.M. Chlorine disinfection chemistry of aromatic compounds. Polynuclear aromatic hydrocarbons rates, products, and mechanisms. Environ. Sci. Technol, 17(6) 334-342, 1983. 

The endoperoxides of polynuclear aromatic compounds are crystalline soHds that extmde singlet oxygen when heated, thus forming the patent aromatic hydrocarbon (44,66,80,81). Thus 9,10-diphenyl-9,10-epidioxyanthrancene [15257-17-7] yields singlet oxygen and 9,10-diphenylanthracene. 

Rubbers. Plasticizers have been used in mbber processing and formulations for many years (8), although phthaHc and adipic esters have found Htde use since cheaper alternatives, eg, heavy petroleum oils, coal tars, and other predominandy hydrocarbon products, are available for many types of mbber. Esters, eg, DOA, DOP, and DOS, can be used with latex mbber to produce large reductions in T. It has been noted (9) that the more polar elastomers such as nitrile mbber and chloroprene are insufficiendy compatible with hydrocarbons and requite a more specialized type of plasticizer, eg, a phthalate or adipate ester. Approximately 50% of nitrile mbber used in Western Europe is plasticized at 10—15 phr (a total of 5000—6000 t/yr), and 25% of chloroprene at ca 10 phr (ca 2000 t/yr) is plasticized. Usage in other elastomers is very low although may increase due to toxicological concerns over polynuclear aromatic compounds (9). 

Extraction Solvent. Dimethyl sulfoxide is immiscible with alkanes but is a good solvent for most unsaturated and polar compounds. Thus, it can be used to separate olefins from paraffins (93). It is used in the Institute Fransais du Pntrole (IFF) process for extracting aromatic hydrocarbons from refinery streams (94). It is also used in the analytical procedure for determining polynuclear hydrocarbons in food additives (qv) of petroleum origin (95). 

Other polynuclear hydrocarbons may include bridged hydrocarbons, spiro hydrocarbons, mixed systems containing alicyclic and aromatic rings, and aliphatic chains, etc. Examples may be found in the CRC Handbook [63, Section C]. Physical properties of selected polynuclear aromatic compounds are given in [49, p. 967]. 

Binuclear aromatic hydrocarbons are found in heavier fractions than naphtha. Trinuclear and polynuclear aromatic hydrocarbons, in combination with heterocyclic compounds, are major constituents of heavy crudes and crude residues. Asphaltenes are a complex mixture of aromatic and heterocyclic compounds. The nature and structure of some of these compounds have been investigated. The following are representative examples of some aromatic compounds found in crude oils ... 

A higher steam/hydrocarhon ratio favors olefin formation. Steam reduces the partial pressure of the hydrocarbon mixture and increases the yield of olefins. Heavier hydrocarbon feeds require more steam than gaseous feeds to additionally reduce coke deposition in the furnace tubes. Liquid feeds such as gas oils and petroleum residues have complex polynuclear aromatic compounds, which are coke precursors. Steam to hydrocarbon weight ratios range between 0.2-1 for ethane and approximately 1-1.2 for liquid feeds. 

Bay, Massachusetts. Gas liquid chromatography was used to detect hydrocarbons present at different depths in the sediment, while low resolution mass spectrometry was employed to measure concentrations of paraffins, cycloparaffins, aromatics and polynuclear aromatics. Their data show that the concentrations of total and saturated hydrocarbons decreased with increased depth, and it was noted that identification and quantification of hydrocarbons in oil-contaminated sediments is required if the fate of these compounds in dredge spills is to be determined. 

This aldehyde synthesis is applicable to compounds of the aromatic series having a labile hydrogen atom (phenyl ethers,1 naphthols,2 dialkylanilines,3-4 naphthostyril,2 anthrones 2) and to certain hydrocarbons of requisite reactivity (anthracene,5-6 7 1,2-benzanthracene,6 3,4-benzpyrene,3 7 pyrene,8 styrene,9 and a, a-diarylethylenes 9). With polynuclear hydrocarbons the best results are secured by the use of a solvent such as o-dichloro-benzene. 9-Anthraldehyde has also been prepared by the action of hydrogen cyanide and aluminum chloride on anthracene in chlorobenzene.10... 

N-nitrosothiazolidine-4-carboxylie acid N-nitrosothiazolidine polynuclear aromatic hydrocarbons polynuclear aromatic compounds peroxy acetyl nitrate... 

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... 

Corannulene is the simplest example within the class of polynuclear aromatic compounds with curved surfaces that are related by carbon framework to the i fullerenes. These aromatic hydrocarbons possess bowl-shaped geometries, consist... 

The vendor claims that the Ariel SST can process soils at rates up to 400% higher than an incineration process. They also state that the technology has been applied to all ranges of petroleum contaminants, including crude oil, as well as nonchlorinated hydrocarbons, chlorinated hydrocarbons, chlorinated pesticides, and polynuclear aromatic compounds. 

Later, D. W., C. W. Wright, K. L. Loening, and J. E. Merritt, Systematic Nomenclature of the Nitrogen, Oxygen, and Sulfur Functional Polycyclic Aromatic Compounds, in Polynuclear Aromatic Hydrocarbons Nomenclature Guide (K. Loening, J. Merritt, D. Later, and W. Wright, Eds.), pp. 27-47, Battelle Press, Columbus, OH, 1990. 

Lee-Ruff, E., and C. Wang, Photooxidation of 6-Methylbenzo-[a]pyrene and Related Compounds, in Polycyclic Aromatic Compounds, Proceedings of the Thirteenth International Symposium on Polynuclear Aromatic Hydrocarbons (P. Garrigues and M. Lamotte, Eds.), Bordeaux, France, October 1-4, 1991, pp. 93-101. 

Polynuclear aromatic hydrocarbons (PAH) are aromatic compounds that contain two or more benzene rings fused together. These substances may be analyzed by HPLC, GC, GC/MS and enzyme immunoassay techniques. The latter is a rapid screening method that may be applied for a qualitative or semiquanti-tative determination Test kits are commercially available for such screening. U.S. EPA (1995) has specified a method (Draft Method 4035) that detects a range of PAHs to different degrees and measures the composite of individual responses to determine the total PAHs in the sample. 

Means, J.C., Hassett, J.J., Wood, S.G., Banwart, W.L., Ali, S., Khan, A. (1980) Sorption properties of polynuclear aromatic hydrocarbons and sediments Heterocyclic and substituted compounds. In Polynuclear Hydrocarbons Chemistry and Biological Effects. Bjorseth, A., Dennis, A.J., Editors, pp. 395 404, Ann Arbor Sci. Publishers, Ann Arbor, MI. 

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