Upgrading, gasoline

References Debuisschert, Q., P. Travers and V. Coupard, "Optimizing Pyrolysis Gasoline Upgrading," Hydrocarbon Engineering, June 2002. 

Upgrading pyrolysis gasoline Upgrading steam cracker C3 cuts Upgrading steam cracker cuts... 

Experimental data have shown that most parts of isoalkanes are concentrated in the gasoline fraction of the liquid product of oil radiation processing. According to this interpretation, intense radiation-enhanced isomerization should be observed in the presence of heavy aromatics in the case of low-dose-rate gamma irradiation of aromatic-rich hydrocarbon mixtures at lowered temperatures. This effect was effectively used for gasoline upgrading (Zaikin and Zaikina 2007). 

Zaikin, Y.A. and Zaikina, R.F. 2007. Effect of radiation-induced isomerization on gasoline upgrading. In Proceedings of the 8th Topical Meeting on Nuclear Applications and Utilization of Accelerators AAAPP 07, Pocatello, ID, July 29-August 2, pp. 993-998. 

Diebold J, ScahiU J. Biomass to gasoline—upgrading pyrolysis vapors to aromatic gasoline with zeolite catalysis at atmospheric-pressure. ACS Symp Ser 1988 376 264—76. 

We shonld also utilize liquid hydrocarbons, which frequently accompany natural gas. These so-called natural gas liquids currently have little use besides their caloric heat value. They consist mainly of saturated straight hydrocarbons chains containing 3-6 carbon atoms, as well as some aromatics. As we found (Chapter 8), it is possible by superacidic catalytic treatment to upgrade these liquids to high-octane, commercially usable gasoline. Their use will not per se solve our long-... 

Natural Gas Upgrading via Fischer-Tropsch. In the United States, as in other countries, scarcities from World War II revived interest in the synthesis of fuel substances. A study of the economics of Fischer synthesis led to the conclusion that the large-scale production of gasoline from natural gas offered hope for commercial utiHty. In the Hydrocol process (Hydrocarbon Research, Inc.) natural gas was treated with high purity oxygen to produce the synthesis gas which was converted in fluidized beds of kon catalysts (42). 

The normal paraffins produced are raw materials for the manufacture of biodegradable detergents, plasticizers, alcohols, and synthetic proteins. Removal of the / -paraffins upgrades gasoline by improving the octane rating. 

LNG—consisting of ethane, propane, butane, and natural gasoline (condensate)—arrives at the plant for upgrading before it is sent to petrochemical plants and refineries as feedstock. Residue gas is sold to the interstate and intrastate pipeline network. MESA, one of the world s major crude helium producers, also delivers helium to a pipeline operated by the U.S. Bureau of Mines. 

Upgrade lower-value materials such as heavy residues to more valuable products such as naphtha and LPG. Naphtha is mainly used to supplement the gasoline pool, while LPG is used as a fuel or as a petrochemical feedstock. 

Figures 1-1 through 1-3 contain sketches of typical unit configurations offered by some licensers. Although the mechanical configuration of individual FCC units may differ, their common objective is to upgrade low-value feedstock to more valuable products. Worldwide, about 45% of all gasoline comes from FCC and ancillary units, such as the alkylation unit.

A number of refiners split the debutanized gasoline into light and heavy gasoline. This optimizes the refinery gasoline pool when blending is constrained by sulfur and aromatics. In a few gasoline splitters, a third heart cut is withdrawn. This intermediate cut is low in octane and it is processed in another unit for further upgrading. 

At the low-molecular-weight end of the spectrum, a process newly commercialized by Mobil for converting methanol into gasoline has significantly expanded opportunities in C-1 chemistry— the upgrading of one-carbon molectrles to mrrlticarbon products. The process involves the use of ZSM-5, a shape-selective zeolite catalyst. (See "Zeolite and Shape-Selective Catalysts" in Chapter 9.)... 

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