Paraffin hydrocarbon Alkanes

Hydrocarbons are the least polar of natural compounds but they form an important class of substances found in oils. The paraffinic hydrocarbons (alkanes) are the most important group. 

Alkylation combines lower-molecular-weight saturated and unsaturated hydrocarbons (alkanes and alkenes) to produce high-octane gasoline and other hydrocarbon products. Conventional paraffin-olefin (alkane-alkene) alkylation is an acid-catalyzed reaction, such as combining isobutylene and isobutane to isooctane. 

An older name for alkanes is paraffin hydrocarbons Paraffin is derived from the Latin words parum affims ( with little affinity ) and testifies to the low level of reactivity of alkanes... 

Fischer-Tropsch Process. The Hterature on the hydrogenation of carbon monoxide dates back to 1902 when the synthesis of methane from synthesis gas over a nickel catalyst was reported (17). In 1923, F. Fischer and H. Tropsch reported the formation of a mixture of organic compounds they called synthol by reaction of synthesis gas over alkalized iron turnings at 10—15 MPa (99—150 atm) and 400—450°C (18). This mixture contained mostly oxygenated compounds, but also contained a small amount of alkanes and alkenes. Further study of the reaction at 0.7 MPa (6.9 atm) revealed that low pressure favored olefinic and paraffinic hydrocarbons and minimized oxygenates, but at this pressure the reaction rate was very low. Because of their pioneering work on catalytic hydrocarbon synthesis, this class of reactions became known as the Fischer-Tropsch (FT) synthesis. 

Paraffin hydrocarbons (Section 2.18) An old name for alkanes and cycloalkanes. 

Propane (C.Hg) is one of the saturated open-chain hydrocarbons that form the paraffin or alkane series... 

Ethane is an important paraffinic hydrocarbon intermediate for the production of olefins, especially ethylene. It is the second member of the alkanes and is mainly recovered from natural gas liquids. 

It has been generally accepted that the thermal decomposition of paraffinic hydrocarbons proceeds via a free radical chain mechanism [2], In order to explain the different product distributions obtained in terms of experimental conditions (temperature, pressure), two mechanisms were proposed. The first one was by Kossiakoff and Rice [3], This R-K model comes from the studies of low molecular weight alkanes at high temperature (> 600 °C) and atmospheric pressure. In these conditions, the unimolecular reactions are favoured. The alkyl radicals undergo successive decomposition by [3-scission, the main primary products are methane, ethane and 1-alkenes [4], The second one was proposed by Fabuss, Smith and Satterfield [5]. It is adapted to low temperature (< 450 °C) but high pressure (> 100 bar). In this case, the bimolecular reactions are favoured (radical addition, hydrogen abstraction). Thus, an equimolar distribution ofn-alkanes and 1-alkenes is obtained. 

Methane, also referred to as marsh gas, is a gas composed of carbon and hydrogen with a chemical formula of CH4. It is the first member of the paraffin or alkane series of hydrocarbons. It is lighter than air, colorless, odorless, tasteless and is flammable. It occurs in natural gas and as a by-product of petroleum refining. In atmospheric burning no smoke production normally occurs. In air methane bums with a pale, faintly luminous flame. With excess air carbon dioxide and water vapor is formed during combustion, with an air deficiency carbon monoxide and water is formed. It forms an explosive mixture with air over a moderate range. Its primary uses are as a fuel and raw feedstock for petrochemical products. 

Several methodologies can be used to identify not only crude or refined product type, but also the brand, grade, and, in some instances, the source crude. The petroleum industry has yielded conventional methods for the characterization of refined products. The simplest is the routine determination of API gravity and development of distillation curves where NAPL is present. More sophisticated methods include gas chromatography and statistical comparisons of the distribution of paraffinic or n-alkane compounds between certain C-ranges. With increased degradation and decomposition, the straight-chain hydrocarbons ( -alkanes) become less... 

Alkyls are paraffinic hydrocarbon groups (but not stand-alone compounds) derived from alkanes by dropping one hydrogen from the formula, resulting in -CnH2n+i. such as the ethyl or propyl groups. 

Alkyl. A paraffinic hydrocarbon group derived by dropping a hydrogen atom from an alkane, CnH2n+i- For example, the methyl alkyl is CH3- ethyl is C2H5-. Groups such as this are often represented in the literature by the letter R-. 

ALKANE. Term for saturated aliphatic hydrocarbon (paraffin hydrocarbon). 

The reaction of sulfur dioxide and chlorine with paraffin hydrocarbons to yield alkane sulfonyl chlorides (RH + S02 + Cl2 - RS02C1 + HC1) (the Reed reaction) was patented in 1939.221 This reaction has usually been run in the liquid phase under strong illumination with short wavelength visible or ultraviolet light.107,218 267... 

Hydrocarbons that contain only single bonds. They are also called alkanes or paraffin hydrocarbons. 

As their name implies, chlorinated paraffins are chlorinated derivatives of paraffinic hydrocarbons. They are referred to in this review as polychlorinated alkanes (PCAs) because they are produced by chlorination of n-alkane feedstocks. Commercial PCA mixtures fall into different categories C10-C13 (short), C 4-C17 (medium) and C2o-C30 (long). These mixtures are further subcategorized into their weight content of chlorine 40-50%, 50-60%, and 60-70% [1,2]. Knowledge of the environmental chemistry of PCAs is needed because the physical properties of short and medium chain mixtures are similar to those of the... 

That the surface tensions of solutions of d- and /-optical isomers aredififerent seems doubtful. Surface tensions of normal alkanes (paraffin hydrocarbons) containing n atoms of carbon are given by a —l4-6 log ( —3)+ll 52 within experimental error. 

Additionally, classes (or types) of hydrocarbons were, and still are, determined based on the capability to isolate them by separation techniques. The four fractional types into which petroleum is subdivided are paraffins, olefins, naphthenes, and aromatics (PONA). Paraffinic hydrocarbons include both normal and branched alkanes, whereas olefins refer to normal and branched alkenes that contain one or more double or triple carbon-carbon bonds. Naphthene (not to be confused with naphthalene) is a term specific to the petroleum industry that refers to the saturated cyclic hydrocarbons (cycloalkanes). Finally, the term aromatics includes all hydrocarbons containing one or more rings of the benzenoid structure. 

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