• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Aluminium and its Extraction

Extracts from this document...


EXTRACTION OF ALUMINIUM Bauxite is an orange-red igneous rock, which occurs naturally in the lithosphere, from which Aluminium is extracted. It contains 30-54% alumina, Al2O3 and other impurities such as clay, Iron (III) Oxide (Fe2O3), Silica (SiO2), and Titania (TiO2). Australia was the top producer of bauxite in 2007, with almost one-third world share. The Bauxite has to be purified by a process known as The Bayer Process. The Bayer process is the main industrial method of refining bauxite to produce alumina. The Bauxite rocks are crushed to smaller rock sizes. Then the bauxite is digested by mixing it with a hot solution of sodium hydroxide, NaOH at 175oC. This only dissolves the oxides of aluminium and silicon, but not the other impurities. The solution is further purified by filtering out the solid impurities. Carbon dioxide gas is then bubbled through the solution, which creates a weak carbonic acid, neutralising the solution and causing the aluminium oxide to precipitate, but leaving the other silicon impurities. The remaining solution is filtered once again and boiled to remove the water. The resultant product is purified aluminium oxide. After the purified aluminium oxide has been produced, the aluminium can be separated by a process known as The Hall-Heroult method. ...read more.


Another factor is the size of the ore body, it needs to be large enough to make sure that profitcs can be made, small ore-bodies may not even cover the start up costs. - The Concentration of metal in the ore body . A large high-grade ore body is economical to mine becuase it conctains a high concentration of the metal in the ore. Some low-grade (i.e. low concentration) deposits may still be economoical to mine if they are large enough and suitably located. Another way low-grade and uneconomical mines becomes efficient if new technologies are invented. The more lower concentration, the more expensive it is to mine. - Mining companies may need to build a railway line from the mining site to the cost, to be able to export the metal extracted. The more remotely located the mine, the greater cost in production. - The cost of producing alumiinium isalso based on how much money was intitially spent on initiaiting the mining operation. This includes the costs of exploration, the establishmnet of the extraction plant (purchasing of machinery and sites for disposal of waste). There are also ongoing costs such as miner's saleries and housing for their families. ...read more.


Hence less green house gases are released since the fuel is being used at a decreasing rate. Recycling aluminium crap to create cars means that approximately 95% of greenhouse gas emissions are saved. In the recycling of aluminium, the smelting process needs about 65000 MJ of energy, unlike recycling which only requires 800 MJ. There is no need for combustion reactions, or electrolysis in the recycling processes, thus the major energy usages in the extraction of metals is saved. This leads directly to the next important reason to recycle metal. Metals like aluminium are a non-renewable resource as they take many thousands even millions of years to form. Aluminium is widely used in modern society because of both its physical and chemical properties. The main physicals properties of aluminium are that it is cheap (mainly because of its abundance) and that is light and malleable. Aluminium also is relatively unreactive compared to other metals, because of the oxide layer that is formed on top. The most common use of aluminium is in soft drink cans, because it is readily rolled, lightweight, odourless, and tasteless and it conducts heat away from the drink so it can be chilled. As more aluminium is recycles that means that less mines are needed, so that means less fluoride compounds are released during the production of aluminium. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Inorganic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Inorganic Chemistry essays

  1. Peer reviewed

    Determining the concentration of acid in a given solution

    5 star(s)

    If there was more sodium carbonate in the flask before I added my known mass, then the concentration would be higher than I calculated. This would mean that more acid would be needed to neutralise it, and I would think that the acid had a lower concentration than it actually did.

  2. Peer reviewed

    Deducing the quantity of acid in a solution

    5 star(s)

    Also, they are very light and it is possible to be watching the meniscus whilst adding solvent. Quantities of materials needed: * 2.65g of Na2CO3 * Approximately 250cm3 of distilled water Procedure: Using an electronic balance, which is quite accurate because it can measure to 2 decimal places, we will weigh 2.65 g of Na2CO3 by difference.

  1. effects Concentration and Temperature on the Rate of Reaction

    For the concentrations of the other reactants used in this reaction I decided to alter them by the same amount and in the same range as I have chosen to alter the concentration of potassium bromide. This ensures that the experiment is as fair as possible, as all reactants are being varied by the same amount.

  2. ethanedioate complex of iron

    Then few more drops of tin(II) chloride were added . Once the solution was cooled to room temperature, one portion 10cm3 of mercury(II) chloride solution was added quickly. 10cm3 of 40% phosphoric acid and 10 drops of barium diphenylamine sulphonate indicator solution were added to the reduced solution.

  1. Titrations in Modern Industrial Laboratories

    Titrations in Modern Industrial Laboratories It is important to prepare an accurate concentration of a standard solution. The concentration of a standard solution must also be correct, so the determinations of vitamins are correct. It is useful to prepare the standard solution before carrying the titration out first, as you

  2. Dipoles and their importance

    The larger the atoms in a molecule, the higher the probability that an instantaneous dipole will exist as the electron cloud will be bigger and further from the nuclei so therefore the electrostatic attraction holding the electrons in place will be weaker and they would be more free to move,

  1. The Effects of Strong and Weak Acids on the Order of a Reaction.

    My one problem was, however, the reaction occurring too fast for me to monitor. I then decided to dilute the 2M of acid into 1M by adding 4cm3 of water and halving the volume. The addition of water without the removal of half was doubling the volume as well as diluting the acid.

  2. easy e

    Pip is the only child except for when he meets Estella. When Pip was a young child he was sent to Miss Havisham's to go to play, this is where he met Estella. When Pip gets to the house Estella is to escort him in, when she meets Pip she calls him 'boy' repeatedly and looks down on him.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work