Isoparaffinic fuel

We cite isomerization of Cs-Ce paraffinic cuts, aliphatic alkylation making isoparaffinic gasoline from C3-C5 olefins and isobutane, and etherification of C4-C5 olefins with the C1-C2 alcohols. This type of refinery can need more hydrogen than is available from naphtha reforming. Flexibility is greatly improved over the simple conventional refinery. Nonetheless some products are not eliminated, for example, the heavy fuel of marginal quality, and the conversion product qualities may not be adequate, even after severe treatment, to meet certain specifications such as the gasoline octane number, diesel cetane number, and allowable levels of certain components. 

The cetane number of a fuel depends on its hydrocarbon composition. In general, normal paraffins have high cetane numbers, isoparaffins and aromatics have low cetane numbers, and olefins and cycloparaffins fall somewhere in between. Diesel fuels marketed in the United States have cetane numbers ranging between 35 and 65. Most manufacturers specify a minimum cetane number of 40—45. 

Lower cloud point in the diesel fuel. Isoparaffins in the light cycle oil boiling range improve the cloud point. 

Chemical and Physical Properties Petroleum fuels contain paraffins, isoparaffins, naphthenes, and aromatics, plus organic sulfur, oxygen, and nitrogen compounds that were not removed by refining. Olefins are absent or negligible except when created by severe refining. Vacuum-tower distillate with a final boiling point equivalent to 730 to 840 K (850 to 1050°F) at atmospheric pressure may contain from 0.1 to... 

High Octane Fuels Without Hydrogenation, The Addition of Olefins to Isoparaffins in the Presence of Sulfuric Acid, J. Petrol. Technol. (1938) 303. 

Alkylation—A refinery process for chemically combining isoparaffin with olefin hydrocarbons. The product, alkylate, has a high octane value and is blended with motor and aviation gasoline to improve the antiknock value of the fuel. 

Alkylation Refinery process for the production of high-octane fuel from the reaction of an olefin and isoparaffin in the presence of an acid catalyst. 

The compositional analysis is an essential part of the quality evaluation of petroleum-derived fuels. The concentration of different compound types such as paraffin, isoparaffin, olefin, naphthene and aromatic are routinely determined by gas chromatography (FIONA analysis), and can be rapidly measured by proton NMR spectroscopy. 

Modification of ZSM-5 zeolite can result in improved liquid yields and a doubling of the isoparaffin index of the liqnid fuels which indicates higher liquid quality compared with the parent ZSM-5 zeolite. The high catalytic activity of modified ZSM-5 was explained by its nniqne acidic properties with a sharp increase of the number and strength of weak acid sites and a decrease of strong acid sites [13]. 

It is used as a solvent and raw material for organic synthesis reactions and is a very important chemical in the petroleum industry. It is also widely used in the rubber and paper processing industries. Isooctane, along with other n- and isoparaffins, are used in the blending of fuels to achieve desired antiknock properties. A total of 17 isomers of octane are known to exist isooctane (2,2,4-trimethylpentane) is a principal ingredient of gasoline. 

The developing kidney is subject to attack by a number of environmental toxins. These include lead, cadmium, uranium, mercury, decalin, JP-5 jet fuel (a mixture of Cl2-15 straight and branched hydrocarbons), Cl0-11 isoparaffinic hydrocarbons, 2,2,4-trimethylpentane, c/-limonene, diethylene glycol, and hexachlorocyclohexane. ... 

Alkylation was first practiced for gasoline production about 60 yr ago. At that time, most of the alkylate was used as fuel for the airplanes used in World War II. Four quite distinct reactors were developed in which isobutane and olefins were introduced as liquids to the reactor. In the reactor, the hydrocarbon liquids are contacted with either liquid sulfuric acid or liquid hydrofluoric acid (HF), which acts as a catalyst. Dispersions of these two relatively immiscible liquids are formed. The alkylate product formed is a mixture of mainly C5-C16 isoparaffins. Alkylate products often have research octane numbers (RONs) varying from 93 to 98 (the motor octane numbers tend to be two to three units lower). 

Because of the catalyst shape selectivity, most products are methyl-branched iso-olefins. Tn the Cg to CJ0 range, branched iso-olefins have good octane rating. In the CJ0 to CJ0 range isoparaffins have good distillate fuel properties after hydrogenation. 

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