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The rate of cracking and the end products are strongly dependent on the temperature and presence of catalysts. Cracking is the breakdown of large hydrocarbons into smaller, more useful alkanes and alkenes. Simply put, hydrocarbon cracking is the process of breaking long-chain hydrocarbons into short ones. This process requires high temperatures ...
Steam cracking is a petrochemical process in which saturated hydrocarbons are broken down into smaller, often unsaturated, hydrocarbons. It is the principal industrial method for producing the lighter alkenes (or commonly olefins ), including ethene (or ethylene ) and propene (or propylene ).
[1] [2] [3] The cracking of petroleum hydrocarbons was originally done by thermal cracking, now virtually replaced by catalytic cracking, which yields greater volumes of high octane rating gasoline; and produces by-product gases, with more carbon-carbon double bonds (i.e. alkenes), that are of greater economic value than the gases produced by ...
Skeletal isomerization occurs in the cracking process, used in the petrochemical industry to convert straight chain alkanes to isoparaffins as exemplified in the conversion of normal octane to 2,5-dimethylhexane (an "isoparaffin"): [4] Fuels containing branched hydrocarbons are favored for internal combustion engines for their higher octane ...
Alkanes have the general chemical formula C n H 2n+2. The alkanes range in complexity from the simplest case of methane (CH 4), where n = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane (C 50 H 102) or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (C 14 H 30).
Relative to thermal cracking of alkanes, oxidative dehydrogenation (ODH) is of interest for two reasons: (1) undesired reactions take place at high temperature leading to coking and catalyst deactivation, making frequent regeneration of the catalyst unavoidable, (2) thermal dehydrogenation is expensive as it requires a large amount of heat ...
[12] [page needed] Chlorination requires finesse, lest it affect the Pt or Re component. The platinum and/or rhenium are very susceptible to poisoning by sulfur and nitrogen compounds. Therefore, the naphtha feedstock to a catalytic reformer is always pre-processed in a hydrodesulfurization unit which removes both the sulfur and the nitrogen ...
W n / n = (1 − α) 2 α n−1. where W n is the weight fraction of hydrocarbons containing n carbon atoms, and α is the chain growth probability or the probability that a molecule will continue reacting to form a longer chain. In general, α is largely determined by the catalyst and the specific process conditions.