Crude oil and its value to society

Although jolty rock oil color may tint like earths natural pollution, behind that thick black exterior lies whizz of the most important raw materials on earth.Crude oil is organize when dying kit and caboodles and animals become immediately covered by sediments in seas and swamps. This counteracts them from decaying and as further sediments make water up the plant and animals become buried deeper and deeper. straight off this takes turn up over millions of historic period and immense pressure and pepperiness (120oc) build up and eventually these organisms turn to oil. Now this raw material is assumption the name as a fossil evoke because of the fact that it is the fossils body that atomic number 18 turning into the oil. It sleeping accommodationpot be said that when we ar hot the fossil fuel we argon in fact using the suns thrust which has been stored as chemical energy in the fossils for millions of years. The relative high coulomb content is out-of-pocket t o small microscopic plankton organisms.Coke and PepsiOn average, boisterous oils ar do of the next elements or compounds* Carbon 84%* atomic number 1 14%* Sulfur 1 to 3% (hydrogen sulfide, sulfides, disulfides, elemental sulfur)* Nitrogen less than 1% (basic compounds with amine groups)* Oxygen less than 1% (found in organic compounds such as carbon dioxide, phenols, ket one and notwithstanding(a)s, carboxylic acids)* Metals less than 1% (nickel, iron, vanadium, copper, arsenic)* Salts less than 1% (sodium chloride, magnesium chloride, calcium chloride)Crude oil is a interlocking smor ordnancebord of hydrocarbons which be basically molecules which contain hydrogen and carbon. The hydrocarbons may vary in length and structure, from straight to branching mountain ranges and sound. Now hydrocarbons are the priming why crude oil is so important because it merchant ship do two things.1. Hydrocarbons contain a plentifulness of energy which bath be use by man to do numerous tasks e.g. electricity generation, shipping, heat etc.2. Hydrocarbons plunder take many opposite make ups. The smallest formation of hydrocarbons is methane which is a feature that is lighter than air. Longer chains with 5 or more carbons are liquids whilst very huge formations may be solid like wax. This is the designer why hydrocarbons are so important is because it is so versatile. By chemically cross linking hydrocarbon chains you can produce almost anything from synthetic good-for-naught to Kerosene. In fact 70% of Britains organic chemicals are produced due to the hydrocarbons dumbfound in crude oil.The major(ip) classes of hydrocarbons in crude oils include* Paraffins* usual reflection CnH2n+2 (n is a intact number, ordinarily from 1 to 20)* straight- or branched-chain molecules* can be gasses or liquids at room temperature depending upon the molecule* examples methane, ethane, propane, butane, isobutane, pentane, hexane* Aromatics* habitual formula C6H5 Y (Y is a longer, straight molecule that connects to the benzine ring)* sound structures with one or more rings* rings contain six-spot carbon atoms, with alternating double and single bonds between the carbons* typically liquids* examples benzene* Nap and thenes or Cycloalkanes* general formula CnH2n (n is a whole number usually from 1 to 20)* ringed structures with one or more rings* rings contain only single bonds between the carbon atoms* typically liquids at room temperature* examples cyclohexane, methyl cyclopentane* Other hydrocarbons* Alkenes* general formula CnH2n (n is a whole number, usually from 1 to 20)* linear or branched chain molecules containing one carbon-carbon double-bond* can be liquid or gas* examples ethylene, butene, isobutene* Dienes and Alkynes* general formula CnH2n-2 (n is a whole number, usually from 1 to 20)* linear or branched chain molecules containing two carbon-carbon double-bonds* can be liquid or gas* examples acetylene, butadienes as yet , before we get products such as synthetic rubber the crude oil essential be expressed from its reserves and then bear uponed.Today the star producers of crude oil include, Texas, California, Alaska, Iran, Kuwait, the middle-east etc. As you can see oil can be found all over the world and thereof different extraction methods are put into progress. Before an oil-rig/well is dug, scientific methods are put into place to determine where to find the oil. Gravimeters and magnetometers and seismographs are utilise to identify the subsurface rock formations which could hold crude oil. Drilling for the crude oil can be extremely onerous due to these conditions and is lots a risky process e.g. some wells moldiness be dug 7 miles deep before some oil stores are found. Today much of the oil extraction is located off margin on platforms standing on the ocean bed. In order for the oil to come up to the oil rig it has to be pumped up by using water, gas or air to force it out. once the oil has been composeed it is often transported by tanker or grape vine to the refinery.Crude oil in its raw form is a complex mixture of hydrocarbons where the hydrocarbons are of varied mass, nurse differing boil temperatures and differing lengths. Now as I allow mentioned previously these hydrocarbons can be very utilizable but before we can use them they must be made into smaller more expedient hydrocarbons. This state can be achieved through with(predicate) a process called fractional distillation. The technique for this process uses the differing boiling temperatures of the molecules in the crude oil so that all differing molecules can be free. The long chained hydrocarbons are furrowed down into particularizeer fractions where the boiling point amongst that fraction does not vary immensely. This process takes place in a particularly designed fractional distillation tug.Process1. Crude oil is zap by passing through pipes in a furnace where the oil is heat up to 600 degrees Celsius.2. The oil willing then boil forming evaporation (gas)3. The oil is then fed into the distillation chamber towards the bottom.4. The distillation chamber may be 100m high and consist of vertically stacking rows of steel trays. The trays have many holes (bubble caps) in them to allow the vapor and the liquids to pass through them. The trays will wait on to collect the liquids that form at various heights in the column. The liquids will menstruum down the tray over a wier.5. The reason why the oil is sepa regulated into narrower fractions can be explained by looking at the temperature gradient in the column. At the bottom of the tank it is extremely hot due to the impertinently fed oil vapor and at the top it is cool. As the vapor passes through the tray it will come into contact with a slightly tank car liquid. This causes some of the hydrogen molecules to condense in that tray causing more founder hydrocarbons in the liquid to evaporate. This process will take place at each tray and in each tray a unique narrow take to the woods of hydrocarbons with similar properties will form. After approx 45 condensations and evaporations have taken place the crude oil has been key outd into fractions.6. The collected liquid fractions may any pass to condensers, which cool them further, and then go to storage tanks. Or go to other areas for further chemical processing.The more evaporable hydrocarbons with the low boiling point form at the top of the tank and the least volatile hydrocarbons with high boiling point at the bottom.Once operating the column may be kept in an equilibrium state by maintaining the input of the crude oil at a flow rate which balances the total of the flow rate at which the fractions are removed. When a tight state exists the compositions of the liquid and vapor at any one tray do not vary. This enables the fractions at each tray to be drawn individually when required. from each one tray will contain a narrow range o f fractions with a narrow range of boiling points.The fractional distillation column will separate the crude oil into the following fractions Refinery gasses, gasoline and naphtha, Kerosene, gas ( diesel engine), oil and residue.Refinery gasses rest of simple alkanes containing up to four carbon atoms. They are utilize as fuels or as a source for building other molecules. natural gas Contains Alkanes with 5 10 carbons in the chain and is used in petrol.Naphtha near important source of chemicals for the chemical process industry.Kerosene is used for kibibyte fuel and domestic heating.Gas oil is used as diesel fuel and as a leadstock for gas pedal cracking.Residue used as a source of lubricating oils and wax and bitumen.Bitumen when mixed with crushed stone is the tarmacadam compound used for road surfaces.Although the crude oil has been separated into utilitarian fraction, some of the separated trays can be further processed to form products that are even more recycla ble.Cracking To obtain more useful alkanes and alkenesHeating the oil fractions with a catalyst. Under these conditions it can brake-down high molecular mass alkanes into low molecular mass alkanes as well as alkenes. The cracking is a random process by which both C-H and C-C bonds can be broken. therefore it is possible for by products to be produced like Hydrogen and branched chain alkane isomers.For example Decane can be broken intoCH3CH2CH2CH2CH2CH2CH2CH2CH2CH3(Decane)HCH3CH2CH=CH2 + H3C- C-CH3CH2CH3(But-1-ene) CH3(2-methylpentane)Decane is broken into these two isomers because there is a bigheartedr compulsion for small chain isomers than larger ones.After the cracking the hot vapourised oil fraction and the catalyst behave as a fluid. This is called the fluidized bed. some of the hydrocarbon fraction can be broke down into carbon which can block the pores of the catalyst. We can recycle the catalyst by pumping it into the regeneration chamber where the carbon coke is is suet off in air at high temperatures.IsomerisationIs the process which we use to obtain branched alkanes. The process involves heating the straight chain alkanes with platinum catalyst to form tined chain alkanesCH3CH3CH2CH2CH2CH2CH3 H3C-C-CH2CH3CH3(Hexane) (2,2-dimethylbutane)However these newly formed branched chain alkanes have to be separated from the straight chain alkanes and this is done by a molecular sieve. The sieve is a type of zeolite that has pores through which the straight chain alkanes can pass through but the branched chain alkanes cannot due to there bulky shape and thus they are separated off. The straight chain alkanes may then be recycled to the respondor.ReformingThis involves the conversion of alkanes to cycloalkanes or cycloalkanes to arenes using a bimetallic catalyst. For example a cluster of platinum and rhenium atoms is very effective in removing hydrogen atoms from methylcyclohexane to form methylbenzene.(Methylcyclohexane) (Methylbenzene)A catalyst c ontaining Clusters of iridium atoms and platinum enables conversions of straight chain alkanes to arenesCH3CH2CH2CH2CH2CH3 + 4H2(Hexane)The metal clusters have to be between 1 and 5nm thick and are deposited on an inert game such as aluminum oxide. The Rhenium and the iridium help prevent the build up of carbon deposits which surmount the activity of the catalyst.Why are Alkanes fuels?The reason for this is because of their reaction with oxygen.Alkane (fuel) + Oxygen (or other oxidizer) Oxidation products + ability transferThis basically means that a fuel must react with oxygen to release large amounts of energy and Oxidation products that arent extremely ruinous to mankind. Although different chains of alkanes can produce different energy amounts and byproducts and are used for different purposes, they all comply with this equation. Below I will list the ideal characteristics which all fuels must have.* A fuel must react with an oxidizer to release large amounts of energy.* A Fuel must be oxidized fairly easily, ignite quickly and sustain enthusiastic without further intervention.* A fuel should be readily available, in large quantities and at a reasonable price.* A fuel should not burn to give products that are difficult to dispose of, or are sulfurous and harmful.* A fuel should be convenient to store and transport safely without loss.So obviously different fuels are used in different environments. In Industry For example larger fuels that produce a lot of energy that may give off lots of harmful gasses can be used. This is because in industry it will have the relevant equipment to extract the dangerous fumes and dispose of them safely. In homes however where there wont be the relevant equipment to handle toxic fuels, more environmental friendly fuels can be used like gas. And for transport we have to consider the transporting of fuel issue so petrol which is a liquid can be used rather than more environmental friendly hydrogen as there is a possibi lity of leakage as it is a gas. However the world is subject to change so in 10 years time other fuels maybe used in place of these.Problems with these fuelsThere are various problems with these fuels. One of the major ones is that we as a rural area rely on them too much (Coal, oil and gas). As they are fossil fuels they are in effect none renewable resources. At our rate of consumption it is predicted that these resource will be depleted at heart 100 years.Also the fossil fuels are the raw materials which come out the feed stock for our chemical industry. They can be processed to produce useful products such as Polymers, medicines, solvents, adhesives etc. So how long can we yield to burn our chemical feedstock?There is also the issue of carbon dioxide emissions of these fuels. This is the major contributor to the greenhouse effect which causes the temperature of our environment to increase dramatically. Due to this, precautions are being made to reduce these emissions. Britain has been set a target to reduce its emissions by 35%. This could be achieved by the outright ban of blacken and oil but nations are reluctant to do this as they have become so reliant on these resources.There is also the possibility of a spillage which can pollute rivers and streams and the environment. This can cause shoemakers last to animals and plant life and there is also the enormous cost of cleansing it up after the disaster.If the carbon based fuel does not in all combust in the furnaces, carbon monoxide is produced and this can cause death by interfering with the blood stream.2C + O2 2CO (impartial oxidation to give carbon monoxide)Also southward and atomic number 7 dioxide can be produced which contribute to harmful acid rain. ontogeny of renewable resourcesAs our reserves of fossil fuels are limited we must find alternative sources of energy. In the search for the alternatives, chemists and other scientists are instanter working to develop renewable resources suc h asBiofuelsThis is when plants are braggy to be used directly as fuels e.g. wood, animal waste and plant waste to produce alcohol and using waste products to produce biogas.Advantages Renewable, help to reduce waste, used with simple technology.Disadvantages Not large enough supply to replace fossil fuels at present rate of use.Nuclear Fuels ambit reaction involving the nuclei of isotopes of uranium 235 splitting to produce vast amounts of energy.Advantages No carbon, nitrogen or sulphur as polluting byproducts.Disadvantages Radioactive waste products are difficult to store and treat which is a very expensive process lamentable air flapEnergy of moving air is transferred into the motion of windmills and wind turbinesAdvantages Renewable pollution and waste free can be used in locality where energy is neededDisadvantages Expensive, not reliable, noisy and unsightly to the environmentHydroelectricityWater stored behind dams and waterfalls can be released and generate electri city by turning a generator.Advantages Renewable, predictable, waste free and can be used on large scale.Disadvantages Expensive to install, environmental impact of dams etc.Solar panelsPanels of solar heat collectors, used to heat water in parts of world were sun is plentiful.Advantages Renewable, no pollutionDisadvantages Require a lot of sunshine, Expensive initial cost, Very large scale to be suitable.HydrogenHydrogen is extracted quite cheaply from water by electrolysis and is used as a fuel.Advantages No pollution as water is the only waste product.Disadvantages Too dangerous and explosive, difficult to store and to use for transport or in domestic situations.BibliographyI would like to thank the following books, websites and teachers which I have used information fromMrs. Chapman (teacher)www.Howstuffworks.com (website)Microsoft Encarta 2002 (CD ROM)Cambridge chemistry 1 by Brian Ratcliff (Book)Chemists in context Second edition by GC hill and JS Holman (Book)Please no te that I have used the information in no particular order however the information taken on the button from the resources has been written in italic.Matthew Stothers Chemistry