Heavy oil, cracking

McAfee of Gulf Refining Co. discovered that a Friedel-Crafts aluminum chloride catalyst could catalytically crack heavy oil. 

The cracked oil and gas products, together with steam from the top of the reactor, are introduced into the fractionator where the oil is separated into two fractions, cracked light oil and cracked heavy oil. 

Unsupported particulates, like their powder counterparts, contain active sites without the addition of other catalytic species. Synthetic zeolites and Si02-Al203 catalysts used for cracking heavy oils to gasolines are catalytic due to their acid sites. They are produced by chemical reactions between the various components but can be found in nature. These materials are often modified by chemical techniques such as ion exchange however, the impregnation techniques typical of dispersed catalysts are not used. Promoters can be added to enhance performance. 

In principle, contact coking process fractionators are similar to catalytic cracking process fractionators. However, sometimes the fractionator desuperheating zone is also used for preheating coke-drum feedstock. Contact coking fractionators are difficult to control because of the cyclic nature of the process. Also, thermally cracked heavy oil liquids are susceptible to further molecular condensation. 

Fluidized Catalytic Cracking (FCC) owes its origins to the 1915 discovery by A. M. McAfee of Gulf Refining Co. (now part of Chevron) that a Friedel Craft aluminium chloride catalyst could catalytically crack heavy oil. Since those early days, the vehicle for catalytic cracking has evolved from fixed beds to moving beds to fluidized beds. 

Filler for cracks and fissures, particularly in highways. Mixtures of bitumen, heavy oils, polymer or sulfur are used. 

Production of maleic anhydride by oxidation of / -butane represents one of butane s largest markets. Butane and LPG are also used as feedstocks for ethylene production by thermal cracking. A relatively new use for butane of growing importance is isomerization to isobutane, followed by dehydrogenation to isobutylene for use in MTBE synthesis. Smaller chemical uses include production of acetic acid and by-products. Methyl ethyl ketone (MEK) is the principal by-product, though small amounts of formic, propionic, and butyric acid are also produced. / -Butane is also used as a solvent in Hquid—Hquid extraction of heavy oils in a deasphalting process. 

Pillared clays are smectite minerals or iUite-smectite minerals that have been stmcturaHy modified to contain pillars of stable inorganic oxide. The pillars prop open the smectite stmcture so they have a basal space of approximately 3.0 nm. Typical metals in the pillars include Al, Zr, Ti, Ce, and Fe, and these materials are used in catalytic processes to crack heavy cmde oils (110—112). 

FIG. 23-3 Temperature and composition profiles, a) Oxidation of SOp with intercooling and two cold shots, (h) Phosgene from GO and Gfi, activated carbon in 2-in tubes, water cooled, (c) Gumene from benzene and propylene, phosphoric acid on < uartz, with four quench zones, 260°G. (d) Mild thermal cracking of a heavy oil in a tubular furnace, hack pressure of 250 psig and sever heat fluxes, Btu/(fr-h), T in °F. (e) Vertical ammonia svi,ithesizer at 300 atm, with five cold shots and an internal exchanger. (/) Vertical methanol svi,ithesizer at 300 atm, Gr O -ZnO catalyst, with six cold shots totaling 10 to 20 percent of the fresh feed. To convert psi to kPa, multiply by 6.895 atm to kPa, multiply by 101.3. 

Example 3 Thermal Cracking of Heavy Oils (Visbreaking)... 

Fluidized catalytic cracking (FCC) Heavy oils, Cig- - Fluidized catalyst particles None... 

Texaco gasification is based on a combination of two process steps, a liquefaction step and an entrained bed gasifier. In the liquefaction step the plastic waste is cracked under relatively mild thermal conditions. This depolymerisation results in a synthetic heavy oil and a gas fraction, which in part is condensable. The noncondensable fraction is used as a fuel in the process. The process is very comparable to the cracking of vacuum residues that originate from oil recycling processes. 

ZSM-5 Cracking of cumene and heavy oil Higher cracking activity Higher yield to light olefins [55]... 

Fuel industry is of increasing importance because of the rapidly growing energy needs worldwide. Many processes in fuel industry, e.g. fluidized catalytic cracking (FCC) [1], pyrolysis and hydrogenation of heavy oils [2], Fischer-Tropsch (FT) synthesis [3,4], methanol and dimethyl ether (DME) synthesis [5,6], are all carried out in multiphase reactors. The reactors for these processes are very large in scale. Unfortunately, they are complicated in design and their scale-up is very difflcult. Therefore, more and more attention has been paid to this field. The above mentioned chemical reactors, in which we are especially involved like deep catalytic pyrolysis and one-step synthesis of dimethyl ether, are focused on in this paper. 

Gas oils (petroleum), hydrodesulphurized coker heavy vacuum Gas oils (petroleum), steam cracked Gas oils (petroleum), hydrodesulphurized heavy vacuum Gas oils (petroleum), heavy vacuum... 

In the thermal cracking methods, the higher-boiling petroleum fractions like heavy oils are subjected to high temperature and pressure by which the bigger hydrocarbon molecules break down to yield lower-boiling lighter fractions ... 

As one more common example of liquid fuels present reference may be drawn to liquified petroleum gas (LPG) or bottled gas or refinery gas. This fuel is obtained as a by-product during the cracking of heavy oils or from natural gas. It is dehydrated, desulfurized and traces of odours organic sulfides (mercaptans) are added in order to identify whether a gas leak has occurred. Supply of LPG is carried out under pressure in containers under different trade names. It consists of hydrocarbons of great volatility such that they can occur in the gaseous state under atmospheric pressure, but are readily liquifiable under high pressures. The principal constituents of LPG are n-butane, iso-butane, butylene and propane,... 

Figure 18.18 Experimental and calculated concentrations of Coke (COK) "a ", Asphaltene (ASP) "o and Heavy Oil -i Light Oil (HO+LO) " at 360 °C for the high temperature cracking of Athabasca oil sands bitumen (Drum 20) using mode /.

Takeuchi, C. Fukui, Y. Nakamura, M., and Shiroto, Y., Asphaltene Cracking in Catalytic Hydrotreating of Heavy Oils. 1. Processing of Heavy Oils by Catalytic Hydroprocessing and Solvent Deasphalting. Ind. Eng. Chem. Proc. Des. Dev, 1983. 22(2) pp. 236-42. 

Burton The first commercial process for thermally cracking heavy petroleum fractions to obtain gasoline. Invented in 1912 by W. M. Burton at Standard Oil (Indiana) and operated commercially from 1913 through the 1920s. See also Dubbs. 

COSMOS [Cracking oil by steam and molten salts] A catalytic process for cracking petroleum or heavy oils. The catalyst is a molten mixture of the carbonates of lithium, sodium, and potassium. Developed by Mitsui and piloted in 1977. 

Dynacracking A petroleum cracking process which combines the best features of the "catalytic cracking and Thermal cracking processes. It converts heavy oil feedstocks to fuel gas, gasoline, and fuel oil. No catalyst is used. Developed in the 1950s by Hydrocarbon Research, but not commercialized. 

KK [Kunugi and Kunii] A process for cracking crude petroleum or heavy oil in a fluidized bed, using coke as the heat carrier. Developed originally by Kunigi and Kunii, subsequently improved by the Japanese Agency of Industrial Science with five Japanese companies. Piloted between 1979 and 1982. 

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