The thermal cracking methods are performed by either direct heating exposure to steam. Catalytic cracking methods involve the use of a catalyst to speed up the cracking reaction.
In fluid catalytic cracking, a hot fluid catalyst is used whereas in hydrocracking, hydrogen gas is used at comparatively lower temperatures. Cracking reaction is very important in improving the octane rating of the fuel, which is used to measure the quality of a fuel and its contribution for knocking effect of engines.
Fractional Distillation : Fractional distillation is the process used to separate components in crude oil. Cracking: Cracking is the process used to break down large hydrocarbon molecules into small hydrocarbons. Fractional Distillation : Fractional distillation uses the difference between boiling points of components in a mixture. Cracking: Cracking involves the production of small hydrocarbons to improve the octane rating.
Fractional Distillation : Fractional distillation does not use catalysts. Cracking: Cracking can be done in the presence of catalysts. Fractional Distillation : Fractional distillation depends on the boiling points of hydrocarbons in crude oil. Cracking: Cracking does not depend on the boiling points of hydrocarbons. Crude oil is a major source of hydrocarbons that is used to produce fuels. Since crude oil is a mixture of different components, it should be processed to obtain a better product that has no impurities.
Furthermore, it should be treated in order to obtain highly effective end products. The spectra of OLP and distillation fractions exhibited intense peaks between and cm —1 and between and cm —1 , indicating the presence of aliphatic compounds associated with methylene CH 2 and methyl CH 3 groups. This confirmed the presence of hydrocarbons [ 21 — 24 ].
This is according to the OLP acid value of The spectra of OLP and distillation fractions were exhibited between and cm —1 , a characteristic asymmetrical deformation vibration of methylene CH 2 and methyl CH 3 groups, indicating the presence of alkanes [ 21 — 24 ]. The peaks between and cm —1 for OLP and distillation fractions were characteristic of an angular deformation outside the plane of C—H bonds, indicating the presence of alkenes [ 21 — 24 ].
The spectra of OLP and light diesel fraction exhibited bands between and cm —1 , peaks characteristic of an angular deformation outside the plane of C—H bonds in the methylene CH 2 group, indicating the presence of olefins [ 21 — 24 ]. OLP is composed of The results were in accordance with the low acid values of OLP 3. This is probably caused by the limitation of internal reflux. The yields of distillates and gas decreased along with the column height, while that of bottoms products increased, for experiments with and without reflux.
The yields of distillates and gas increased with increasing catalyst content, while that of bottoms products decreased. The densities of distillation fractions increased with increasing boiling temperature intervals, remaining almost constant along with the column height. In addition, the densities of gasoline, kerosene, and light diesel produced by fractional distillation in laboratory scale with reflux superposed exactly those of kerosene, light diesel, and heavy diesel produced by fractional distillation in laboratory scale without reflux, showing the importance of operating under reflux.
The acid values of distillation fractions showed a tendency to decrease with increasing boiling temperature ranges. In addition, acid values of distillation fractions decreased with increasing Na 2 CO 3 content, for distillation experiments using a column of 50 cm, with and without reflux. Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution 3. Help us write another book on this subject and reach those readers.
Login to your personal dashboard for more detailed statistics on your publications. Edited by Marisa Mendes. Edited by Amal Ali Elkordy. We are IntechOpen, the world's leading publisher of Open Access books. Built by scientists, for scientists. Our readership spans scientists, professors, researchers, librarians, and students, as well as business professionals. Downloaded: Abstract This work aims to investigate the fractional distillation of organic liquid products OLP obtained by catalytic cracking of palm oil Elaeis guineensis Jacq.
Keywords palm oil organic liquid products fractional distillation light diesel. Fractional distillation of OLP 2. Laboratory unit 2. Distillation without reflux: experimental apparatus and procedures The laboratory fractional distillation apparatus was operated without reflux and the procedure is described in detail elsewhere [ 21 ].
Distillation with reflux: experimental apparatus and procedures The fractional distillation of OLP with reflux was performed by using an experimental apparatus similar to that described by Mota et al. Chemical analysis of OLP and distillation fractions 2. Table 1. Table 2. Fractional distillation of OLP 3. Laboratory unit 3.
Table 3. Molecules with "straight chains" have a tendency to pre-ignition. This double explosion produces knocking in the engine. Octane ratings are based on a scale on which heptane is given a rating of 0, and 2,2,4-trimethylpentane an isomer of octane a rating of In order to raise the octane rating of the molecules found in petrol gasoline and so make the petrol burn better in modern engines, the oil industry rearranges straight chain molecules into their isomers with branched chains.
It is used particularly to change straight chains containing 5 or 6 carbon atoms into their branched isomers. Reforming is another process used to improve the octane rating of hydrocarbons to be used in petrol, but is also a useful source of aromatic compounds for the chemical industry. Aromatic compounds are ones based on a benzene ring. Reforming uses a platinum catalyst suspended on aluminium oxide together with various promoters to make the catalyst more efficient.
Isomerisation reactions occur as above but, in addition, chain molecules get converted into rings with the loss of hydrogen.
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