Petroleum cracking gases from

Coke is obtained by destructive distillation or carbonization of bituminous coal, coal-tar pitch and petroleum produced during petroleum cracking. Coke from bituminous coal is used to reduce iron ore in blast furnaces and to produce synthesis gas. Petroleum coke or that obtained from coal-tar pitch is used in electrolytic reduction of aluminum oxide to aluminum and in the preparation of several metal carbides.. ... 

Ethylene (Ethene or Elayl), H2C CH2 mw 28.05 colorless, flammable, dangerous to handle gas with characteristic sweet odor and taste sp gr 0.975 (air = 1.0), mp —169.4°, bp —103.8°, flash p —136°C explosive limits in air, % by vol, lower 3.0 upper 34.0 si sol in w, more in ale sol in eth. Ethylene is a major component of petroleum refinery gas from cracking units, and is sometimes recovered therefrom by distillation or other means. Some pure ethylene is produced by passing hot ethanol vapors over a catalyst, such as activated alumina (Ref 4). Its laboratory prepn consists of heating ethanol in definite proportions with sulfuric acid of certain concns. By using a 90% acid and 90% ale, ethylene can be produced in a regular stream at a yield of 84 to 85% of theory (Ref 2). 

Secondary butyl alcohol, methylethyl car-binol, 2-butanol, CH3CH2CH(Me)OH. B.p. I00°C. Manufactured from the butane-butene fraction of the gas from the cracking of petroleum. Used to prepare butanone. 

The feedstocks used ia the production of petroleum resias are obtaiaed mainly from the low pressure vapor-phase cracking (steam cracking) and subsequent fractionation of petroleum distillates ranging from light naphthas to gas oil fractions, which typically boil ia the 20—450°C range (16). Obtaiaed from this process are feedstreams composed of atiphatic, aromatic, and cycloatiphatic olefins and diolefins, which are subsequently polymerized to yield resias of various compositioas and physical properties. Typically, feedstocks are divided iato atiphatic, cycloatiphatic, and aromatic streams. Table 2 illustrates the predominant olefinic hydrocarbons obtained from steam cracking processes for petroleum resia synthesis (18). 

Hydrogen Hydrogen recovery was the first large commercial membrane gas separation. Polysulfone fiber membranes became available in 1980 at a time when H2 needs were rising, and these novel membranes quickly came to dominate the market. Apphcations include recovery of H2 from ammonia purge gas, and extraction of H2 from petroleum cracking streams. Hydrogen once diverted to low-quality fuel use is now recovered to become ammonia, or is used to desulfurize fuel, etc. H2 is the fast gas. 

Blaugas An early thermal cracking process for making liquid petroleum gas from petroleum. Developed by the German company Blau in Augsburg from 1905. Not to be confused with blue gas (see Water gas). 

FTC [Fluid-bed thermal cracking] A continuous thermal cracking process for making synthesis gas from heavier petroleum fractions. 

Gasmaco [Gas Machinery Company] A process for making a substitute natural gas from petroleum fractions and residues by thermal cracking. Developed from the Hall (2) process in the 1940s by the American Gas Association. See also Petrogas. 

Gas-to-liquids (GTL) is the chemical conversion of natural gas into petroleum products. Gas-to-liquid plants use Fischer-Tropsch technology, which first converts natural gas into a synthesis gas, which is then fed into the Fischer-Tropsch reactor in the presence of a catalyst, producing a paraffin wax that is hydro-cracked to products (see also Chapter 7). Distillate is the primary product, ranging from 50% to 70% of the total yield. 

Residual fuel oils and heavy marine fuels are composed of high-boiling-petroleum fractions, gas oils and cracked components. Residual and clarified oil streams from the FCC process can contain degraded alumina/silica catalyst fines. These 20- to 70-micron-diameter fines are known to contribute to a variety of problems in fuel injection and combustion systems. In marine engines, excessive injector pump wear, piston ring wear, and cylinder wall wear can all be due to the abrasive action of catalyst fines on these fuel system parts. 

Synonym marsh gas Formula CH4 MW 16.04 CAS [74-82-8] prime constituent of natural gas formed from petroleum cracking, decay of animal and plant remains, and anaerobic fermentation of municipality landfill contents occurs in marshy pools, landfill gas, and leachate from the landfill colorless and odorless gas lighter than air gas density 0.717 g/L liquefies at-161.4°C soluble in organic solvents, slightly soluble in water (25 mg/L) flammable gas. 

The most basic raw petrochemical materials are liquefied petroleum gas, natural gas, gas from cracking operations, liquid distillate (C4 to C6), distillate from special cracking processes, and selected or isomerized cyclic fractions for aromatics. Mixtures are usually separated into their components at the petroleum refineries, then chemically converted into reactive precursors before being converted into salable chemicals within the plant. 

As in the acetaldehyde process, this can be carried out commercially in either a single-step or a two-step process. The latter is economically more favourable because a propylene/propane mixture (made by petroleum cracking) can be directly used as the feedstock. Propane behaves like an inert gas and does not participate in the reaction. Acetone is separated from lower and higher boiling compounds in a two-step distillation. 

Chemical intermediates are listed first in Table 1.1. These are the chemicals that are used to synthesize other chemicals, and are generally not sold to the public. For example, ethlyene is an intermediate produced from hydrocarbons by cracking natural gas derived ethane or petroleum derived gas oil, either thermally using steam or catalytically. Ethlyene is then used to produce polyethylene (45%), a polymer and ethlyene oxide (10%), vinyl chloride (15%), styrene (10%), and... 

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