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Organic Chemistry. Fossil Fuels. Fossil Fuels. Fossil fuels form the major part of our fuel resources They are derived from the fossil remains of living organisms which have been altered by heat and pressure. World Proven Reserves of Crude Oil. 65.4. 20.6. 63.7. 44.0. 675.7. 74.9. 89.5.
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Organic Chemistry Fossil Fuels
Fossil Fuels • Fossil fuels form the major part of our fuel resources • They are derived from the fossil remains of living organisms which have been altered by heat and pressure
World Proven Reserves of Crude Oil 65.4 20.6 63.7 44.0 675.7 74.9 89.5 thousand million barrels
World Proven Crude Oil Reserves as percent of 1296 thousand million barrel total
Natural Gas • Formed in large deposits under the sea, usually together with petroleum • 90% methane and needs very little treatment before use. • Used mainly for heating houses and energy production • Piped from the deposit to the land
Coal • Vast deposits of coal in the Latrobe Valley Victoria are used to produce electricity.
Oil • Crude oil is the petroleum that is pumped directly from the ground. • It is a complex mixture of hydrocarbons with one or two carbon atoms up to a limit of about 50 carbon atoms. • This is usually not useful, so it must separated by distillation.
Crude Oil • This is a main part of this section due to it being used widely, all over the world, however is a non-renewable source. It is a mixture of chemicals that are not chemically bonded (hence it is a mixture), but are still together. • A hydrocarbon - A molecule that contains only hydrogen and carbon • Alkane - A saturated hydrocarbon • Mixture - More than one substance chemically bonded
Crude oil from the ground is separated into usable groups of hydrocarbons at this refinery. Each petroleum product has a boiling point range, or "cut," of distilled vapors that collect in condensing towers.
Petroleum • Petroleumis a mixture of alkanes, cycloalkanes, and aromatic hydrocarbons. • Petroleum is formed from the slow decomposition of buried marine life, primarily plankton and algae. • As petroleum is formed it is forced through porous rock until it reaches an impervious layer of rock. • Here it forms an accumulation of petroleum and saturated the porous rock creating an oil field.
Petroleum • Petroleum was once used for medicinal purposes. • It was first distilled by running through a whiskey still, in an attempt to make it taste better. • The liquid that he obtained burned quite well in lamps. • This clear liquid that was obtained from petroleum distillation was called kerosene.
Crude oil is a mixture of many different hyrocarbon lengths and we can use fractional distillation to separate them into their separate lengths for their unique uses. The hydrocarbons in crude oil with longer lengths (more carbon atoms) are more viscous and therefore have higher boiling points. This factor means that using the fractions boiling points, the fractionating column can separate out the crude oil according to the different temperatures it boils.
The process is as follows: • Crude oil is pumped into the distillaryvapourised • It enters the column at 340 degrees celcius where the bitumen or residue which is the most viscous condenses, coming out of the bottom • Oil then condenses slighly higher up the tower at 340 degrees celcius. It has a 35 molecule length and is fractioned off away from the rest of the mixture • Next, diesel condenses at 250 degrees celcius with its 20 molecule length where it is filtered out • Kerosene at 180 degrees celcius condenses and is sectioned off with its 15 molecule length • Naptha is next to condense at 110 degrees celcius with 10 molecules in it's chain • Petrol at 40 degrees is sectioned off with 8 molecules • Finally, refinery gas is sectioned off at the top of the tower with it's 3 molecules. This short molecule length is what makes it a gas.
Petroleum products and the ranges of hydrocarbons in each product.
Petroleum delivered from well field Water washing to remove impurities Distillation to separate by boiling point ranges Conversion reactions to alter molecular structures Mixing to obtain maximum commercial characteristics
Petroleum Refining Distillation – separation by boiling point
Conversion Reactions THERMAL CRACK CATALYTIC ALKYLATION COMBINE POLYMERIZATION Dehydrogenation Dehydroisomerization Isomerization Dehydrocyclization Hydrocracking REFORMIING REARRANGE ISOMERIZATION
Review • Complete the revision questions page 188 (40 – 43) • Complete the revision questions page 190 (44 – 46) • Complete the multiple choice questions pages 191 – 192 • Complete the review questions 2, 3, 4, 7, 8, 10, 11, 13, 15, 17, 18 • Complete the exam practice questions