Hydrocarbons thermal cracking selectivity depending on their. One of the byproducts of this thermal decomposition reaction is ethene. Sep 14, 2011 cracking temperature of methane posted in industrial professionals. Cracking temperature of methane posted in industrial professionals. Catalytic cracking of hydrocarbons uniwersytet warszawski. Catalytic cracking presentation cracking chemistry zeolite.
Catalytic cracking of hydrocarbons in a crec riser simulator using a yzeolite based catalyst. Steam cracking plants figures 1 and 2 use a variety of feedstocks, for example. Organic chemistry chemistry of compounds that contain carbon combine mainly with hydrogen, oxygen, and nitrogen over 10 million compounds made with these 4 elements 95% of compounds contain carbon form stable, covalent bonds with each other. Pdf catalytic cracking of hydrocarbons in a crec riser. Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds alkenes. Ppt alkanes, alkenes and cracking powerpoint presentation, free. Cracking takes large hydrocarbons and breaks them into smaller ones. In fact, they serve as building blocks for many familiar plasticspolyethylene, vinyl. The complex alkanes with high molecular weights that are found in crude oil are frequently broken into smaller, more useful alkanes by thermal cracking. In the petroleum industry, large hydrocarbons from the distillation of crude oil are often cracked to split them into smaller bits. Journal of catalysis 10, 277289 1968 hydrocarbon cracking reactions on nickel j. When two ends of a hydrocarbon chain join together naming and drawing cyclic hydrocarbons draw. A free powerpoint ppt presentation displayed as a flash slide show on id. With such capabilities, they can form more complex molecules like cyclohexane and in rare instances aromatic hydrocarbons like benzene.
Ppt cyclic hydrocarbons powerpoint presentation free to. Realworld reading link if you have ridden in a car or a bus, you have used hydrocarbons. Hydrocarbons thermal cracking selectivity depending on. These are hydrocarbons which contain at least one carboncarbon triple bond. Catalytic cracking presentation free download as powerpoint presentation. This website and its content is subject to our terms and conditions. The simplest alkenes have the general formula c n h 2n.
Model the industrial process of cracking larger hydrocarbons to produce smaller alkanes that can be converted into petrol. The alkane c 14h 30 might split in a variety of different ways. Dan you dont have to trust my words about cracking. Actually i am bit confused about the step of reaction. Feed stocks are light and heavy oils from the crude oil distillation unit which are processed primarily into gasoline as well as fuel oil and light gases. Hydrocarbons types, classification, properties, preparation. This unit will cover exothermic and endothermic reactions, rate reaction, oxidation and reduction, electrolysis, testing for ions and gases, fuels, combustion, alkanes and alkenes.
They have a relatively low solubility in water, but are highly lipophilic. The chemistry of carbon compounds is called organic chemistry. The gasoline and diesel fuel that are used in cars, trucks, and. Cracking of ethane and propane to produce ethylene. Cracking cracking is the process whereby complex organic molecules such as kerogens or heavy hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carboncarbon bonds in the precursors. It is when big hydrocarbon molecules are broken down into smaller ones.
Write equations for the cracking of c 14h 30 which lead to the. Hydrocarbon cracking reactions occur in the presence of steam inside the furnace in the radiant coil. Alkanes hydrocarbons containing only single covalent bonds ex. Powerpoint name hydrocarbons iupac rules, multiple bonds subject chemistry resources for high school teachers and students powerpoint lessons, notes, labs, worksheets, handouts, practice problems, and solutions. Cracking of hydrocarbons aqa gcse chemistry 91 teaching. Catalytic cracking uses heat, pressure and a catalyst to break larger hydrocarbon molecules into smaller, lighter molecules. Natural gas and fuels many of the natural fuel sources we use are hydrocarbons.
Hydrocarbons thermal cracking selectivity depending on their structure and cracking parameters introduction 1 1 introduction production of lower olefins, like ethylene and propylene, it is a fundamental process in chemical industry for the reason that the worldwide demand for these compounds is higher than any other chemicals. Cracking temperature of methane industrial professionals. After the fractional distillation of crude oil there are too many large hydrocarbons and not enough small hydrocarbons to meet the publics demand. Starter write a definition for the following terms. Powerpoint name hydrocarbons iupac rules, multiple bonds. A presentation and worksheet on hydrocarbon cracking. Hydrocarbon cracking reactions on nickel sciencedirect. Cracking process involves breaking of cc and ch bonds. This is done by heating the hydrocarbon in the presence of a catalyst. You can change one fraction into another by one of three methods. Cracking hydrocarbons in liquid paraffin with a catalyst. Crude oil global market report 2019 the crude oil market size is expected to grow at a cagr of around 4.
A small amount of carbon and hydrogen are also produced. Hydrocarbons organic compounds that contain only hydrogen and carbon. The rate of cracking and the end products are strongly dependent on the temperature and presence of catalysts. Ppt crude oil refining powerpoint presentation free to. First, crack the vapour of liquid paraffin by passing it over a heated catalyst to produce and collect a mixture of gaseous shortchain hydrocarbons.
Cracking hygdrocarbons presentation teaching resources. Cracking cracking is defined as the process of decomposition of higher molecular weight hydrocarbons higher boiling into lower molecular weight hydrocarbons low boiling. Learn the basics about the cracking of hydrocarbons and why it is done. The petrochemical industry, the industrial production of ethene activity 2. Plastics many of the plastics we use in everyday life and in. In thermal cracking, high temperatures typically in the range of 450c to 750c and pressures up to about 70 atmospheres are used to break the large hydrocarbons into smaller ones.
Cracking is the breakdown of a large alkane into smaller, more useful alkenes. Compounds like methane, butane, propane, and hexane are all hydrocarbons. A gaseous product is obtained which is flammable and which will. Catalytic cracking catalytic cracking catalytic cracking uses heat, pressure and a catalyst to break larger hydrocarbon molecules into smaller, lighter molecules. Cyclic hydrocarbons examples testosterone hydrocarbon ring structures. Meanwhile, cracking of hydrocarbons is a process in which heavy organic molecules are broken down into lighter molecules.
When hydrocarbons burn they are reacting with oxygen in the air. Liquid paraffin a mixture of alkanes of chain length c20 and greater is vaporised and passed over a hot pumice stone catalyst. Hydrocarbons hydrocarbons hydrocarbons hydrocarbons hydrocarbons iupac system of naming organic compounds iupac system of naming organic compounds naming branches as groups naming branches as groups structural isomers how many structural isomers compounds with the. Aug 12, 20 learn the basics about the cracking of hydrocarbons and why it is done. Feedstock reacts with catalyst and cracks into different hydrocarbons. The petrochemical industry, pressure and steam in ethene production activity 3. Thermal cracking gives mixtures of products containing high proportions of. Galwey from the chemistry department, the queens university o belast, northern ireland received june 21, 1967. Section alkanes know that alkanes are saturated hydrocarbons. This is achieved by using high pressures and temperatures without a catalyst, or lower temperatures and pressures in the presence of a catalyst. Unsaturated hydrocarbons hydrocarbons with double or triple bondson the other hand, are quite reactive. There are three basic functions in the catalytic cracking process. Their chemical formulas consist of only carbon and hydrogen atoms, in a variety of ratios and chemical configurations. Ppt chapter 25 alkanes and cracking powerpoint presentation.
Thermal cracking is typically performed at high temperatures, and often in the presence of a catalyst. Realworld reading link if you have ridden in a car or a bus, you have used. Gcse chemistry what is the cracking of hydrocarbons. Catalytic cracking in which a catalyst is employed and which produces high yields of branched and cyclic alkanes. A lesson covering cracking hydrocarbons as part of the organic chemistry unit key stage 4, aqa. Includes a couple of videos summarising the process cracking, and testing for alkenes. Knowledge of thermal cracking of hydrocarbons is important in understanding and modeling petroleum maturation. Includes what cracking is and why it is useful, conditions for thermal and catalytic cracking, testing for alkenes and completing cracking equations. I did the demo of cracking but used the diagram as well. This unit will cover exothermic and endothermic reactions, rate reaction, oxidation and reduction, electrolysis, testing for. Cracking is the name given to breaking up large hydrocarbon molecules into smaller and more useful bits.
Simply put, hydrocarbon cracking is the process of breaking a longchain of hydrocarbons into short ones. Those include dubbs cracking process, burtonhumphreys cracking process, and shukhov cracking process. Cracking of hydrocarbons involves thermal decomposition. Fractional distillation of crude oil industrial cracking thermal. Ethene c 2 h 4 is an example of a family of hydrocarbons called the alkenes. Generally, the rate of cracking and the final products. The important fuels like petrol, kerosene, coal gas, cng, lpg etc. Petroleum and natural gas are the major sources of aliphatic hydrocarbon while coal is an important source of aromatic hydrocarbons. Oct 30, 2012 hydrocarbons organic compounds that contain only hydrogen and carbon. Hydrocarbon cracking is the process whereby large and heavy hydrocarbon molecules longchain hydrocarbons are broken down up into simpler and smaller bits as light hydrocarbons shortchain hydrocarbons by the breaking a carboncarbon bonds in cracking stock. Steam cracking is a petrochemical process in which saturated hydrocarbons are broken down. Hydrocarbons are used mainly as fuels, solvents and lubricants.
Some of the large hydrocarbons the heavier fractions are broken down into more useful smaller hydrocarbons lighter fractions by a process known as cracking. The hydrocarbons which contain at least one special type of hexagonal ring of carbon atoms with three double bond in the alternate positions are called aromatic hydrocarbon. Gcse chemistry what is the chemistry of the cracking of. Thermal you heat large hydrocarbons at high temperatures sometimes high pressures as well until they break apart. This can be attributed to the rising demand for fossil fuels to cater to energy needs from around the world especially in developing countries such as china and india and the expected stabilization of oil and gas prices. Pressure and steam an interesting aspect of ethene production. Then test the mixture for unsaturation with bromine water. Cracking takes place at high temperatures as the large molecules pass over a catalyst. Chemical processing how oil refining works howstuffworks.
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