Gasoline blending components

The cumene product is 99.9 wt % pure, and the heavy aromatics, which have a research octane number (RON) of 109, can either be used as high octane gasoline-blending components or combiaed with additional benzene and sent to a transalkylation section of the plant where DIPB is converted to cumene. The overall yields of cumene for this process are typically 97—98 wt % with transalkylation and 94—96 wt % without transalkylation. 

Polymerization - Polymerization is occasionally used to convert propene and butene to high octane gasoline blending components. The process is similar to alkylation in its feed and products, but is often used as a less expensive... 

The use of acidic chloroaluminates as alternative liquid acid catalysts for the allcy-lation of light olefins with isobutane, for the production of high octane number gasoline blending components, is also a challenge. This reaction has been performed in a continuous flow pilot plant operation at IFP [44] in a reactor vessel similar to that used for dimerization. The feed, a mixture of olefin and isobutane, is pumped continuously into the well stirred reactor containing the ionic liquid catalyst. In the case of ethene, which is less reactive than butene, [pyridinium]Cl/AlCl3 (1 2 molar ratio) ionic liquid proved to be the best candidate (Table 5.3-4). 

Both alkylate and ether have excellent properties as gasoline blending components. They have a low RVP, a high road octane, no aromatics, and virtually zero sulfur. The emphasis on alkylation and etherification will continue in both the U.S. and the rest of the world. 

BUTACRACKING A process for converting iso-butanes to iso-butene, which can then be converted to gasoline-blending components such as methyl /-butyl ether. Developed by Kinetics Technology International. 

Cold Acid A process for polymerizing isobutene, mainly into dimers and trimers, for making high-octane gasoline blending components. It is catalyzed by 60 to 70 percent sulfuric acid at 25 to 35°C. Developed by the Shell Companies. See also Hot Acid. 

The remnant hydrocarbons that are talcen from the top of the mixing vessel are often called benzene raffinatej a misleading, ironic name. Benzene raffinate contains no benzene. Its the leftovers after the goodies are removed, but it is still a good gasoline blending component. 

The aromatics-laden solvent leaves the bottom of the column as a liquid. The vapors leaving the top of the column, the aromatics raffinate, have almost no aromatics left. They are cooled and condensed to a liquid and used elsewhere, normally as a gasoline blending component. 

All the BTXs are high-octane gasoline blending components. In the petrochemicals business, toluene is used as a building block for polyurethane. Para-xylene and ortho-xylene are used to make polyester fibers and plastics, allcyd resins, and plasticizers. 

The butanes are used as gasoline-blending components. Normal butane is sometimes an olefins plant feed. Isobutane is used in refinery alkylation plants with propylene or butylene to make alkylate, a high-octane gasolineblending component. 

Pygas is fractionated to make a Cs heart cut, a stream with the styrene concentrated in it. This is usually done before the pygas is hydrotreated in preparation for using it as a gasoline blending component. Otherwise the styrene would hydrogenate as well. 

Methanol, CH3OH, the simplest alcohol, is made by reacting CO and H2 at high pressures over a catalyst. Methanol is a liquid at room temperature and is highly toxic. It is used to make formaldehyde, acetic acid, and other chemical intermediates. It is also used as a feedstock for MTBE (methyl tertiary butyl ether), a gasoline-blending component. 

Methanol is used primarily to make MTBE, acetic acid, and formaldehyde, and is used as a gasoline blending component or neat as an automotive fuH. 

Figure 5 Alkylation process using sulfuric acid. Butanes and butenes react in the presence of a catalyst (sulfuric acid) to form an alkylate for use as a gasoline blending component. Propane and butane are also produced. (From Ref. 6.)...

Uses. As a gasoline blending component to enhance volatility as a constituent of liquid petroleum gas, which is usually a mixture of... 

Dimerization of other simple alkenes such as propylene and butenes is of practical significance because of the problems associated with the use of MTBE the presently widely used high-octane oxygen blending component. The transformation of low-value streams, such as butenes, into valuable gasoline blending components is particularly attractive. 

The enhanced diffusivity of polynuclear compounds in sc C02 has been utilized to enhance catalyst lifetimes in both 1-butene/isoparaffin alkylations (Clark and Subramaniam, 1998 Gao et al., 1996). The former may be catalyzed using a number of solid acid catalysts (zeolites, sulfated zeolites, etc.), and the use of sc C02 as a solvent/diluent permits the alkylations to be carried out at relatively mild temperatures, leading to the increased production of valuable trimethylpentanes (which are used as high-octane gasoline blending components). The enhancement of product selectivity in the latter process is believed to result from rapid diffusion of ethylbenzene product away from the Y-type zeolite catalysts, thus preventing product isomerization to xylenes. 

Cumene a colorless liquid [C6H5CH (CH3)2] used as an aviation gasoline blending component and as an intermediate in the manufacture of chemicals. 

Tankage equivalent to ten days of SRC-II oil feed, fifteen days of motor gasoline blend components, fifteen days of light products, and ten days of intermediate products. 

Alkylate is a gasoline blending component with exceptional antiknock properties, which seems to avoid the legislative pressure. Alkylate consists exclusively of isoalkanes and is obtained from the C3-C4 cut of the FCC units. In many instances, isobutene from the C3-C4 fraction is transformed selectively with methanol into methyl tert-butyl ether (MTBE). Therefore, a mixture of 1-butene and 2-butene is used for alkylation purposes. The other reactant is isobutane. The major constituents of the alkylate are 2,2,3-, 2,2,4-, 2,3,3- and 2,3,4-trimethyl pentane (TMP). Besides, the alkylate contains other C8 isoalkanes, such as dimethyl hexane (DMH), 3-ethyl 2-methyl pentane, methyl heptane and ethyl hexane, and even isoalkanes with carbon numbers that are not multiples of 4. 

The ether process combines an alcohol with an iso-olefin. In the United States, a weight percentage of oxygenate (2 wt.%) content is mandated for reformulated gasoline (RFG). The most common oxygenate currently used is methyl tertiary butyl ether (MTBE). Methanol and the iso-olefin form of isobutylene are reacted to form MTBE. Other alcohols, such as ethanol, may be reacted with iso-butylene to form ethyl tertiary butyl ether (ETBE). Methanol can be reacted with iso-amylene, another iso-olefin, to form tertiary amyl-methyl ether (TAME). Of all the mentioned ethers, MTBE is the one most widely used as a gasoline-blending component.16... 

Lighter products from the refining of crude have higher value as petrochemical feeds than as gasoline-blending components. In particular, olefins and aromatic compounds possess higher values as petrochemicals than as gasoline components. 

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