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

Biohydrometallurgy is an application in mining.

Extracts from this document...


Biohydrometallurgy "Biohydrometallurgy is an application in mining. In its natural state a metal such as copper is found combined with other elements in the mineral chalcopyrite. A bacterium is then used to form the compound copper sulphate (CuSO4), which in turn can be treated chemically to obtain pure copper. This microbiological mining process is used only with low-grade ores and currently accounts for 10% of copper production world-wide." Copper can be extracted from its ores by using bacteria. This is done by, firstly the low-grade copper ore and also the tailings (left from an earlier traditional mine) are stacked up where the ground has been made impermeable. The ground is then sprayed with the acidic leaching solution (T. ferro oxidans and T. Thio-oxidans). This solution is used because the bacteria used, thrive in acidic conditions and they also don't need any organic material on which to feed. The bacteria require Fe ions, or S ions, oxygen and carbon dioxide. The bacterium may also need bacterial nutrients containing nitrogen and phosphorus. ...read more.


Cyanidation of the final and resulting extract led to a breakthrough, in which the gold recovered increased from 10% to 100%. More research was carried out, as funding became available. A student called Ali Nobar introduced a mixed culture of moderately thermophillic bacteria from certain samples. This culture became effective over a wide range of conditions such as temperatures, pH, water salinity and arsenic concentration. Research found out That the bacteria worked best at 46 degrees c (if the temperature is to high the bacteria cell will became denatured due to a higher temperature) and in solutions with a pH of between 0.5 and 1.5. These greatly enhanced the percentage of gold extraction A graph to show the enhancement of gold recovery using bacteria Key Cyanidation alone Bacterial oxidation followed by cyanidation This new process has many advantages and disadvantages. One of the main advantages of this process is that it cost much less than the traditional method. Mining copper by the traditional method can cost between $130 and $200 per tonne. ...read more.


Also when using the traditional method when extracting copper, more copper can be obtained from the ore. The bacterial process of extracting gold is used as a primary process (secondary process is the traditional method) because the research and technology has been developed fast. More economic because more gold is produced so more money to be made. There is also a low cost of running the plants. Also the whole process is more feasible and economically competitive with the conventional process. For a new process for bacterial leaching to become commercial the government and political powers must approve and also regulate a new process and may need to provide funding. A Political power may need to hold an enquiry into the effects of this new technology to check if it is mandatory and safe. Thus granting permission for the new technology to go ahead. Summary This type of bacterial chemistry in order to obtain metal from its ore is a new technology but the industry is still yet to recognise it. Its main advantage is it cheap and mostly environmentally friendly compared to traditional methods. This type of process will lead us into the future. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Living Things in their Environment 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 GCSE Living Things in their Environment essays

  1. Marked by a teacher

    The effects of disinfectants and antibacterial soap on bacterial growth

    5 star(s)

    Another question that occurred to us after performing the experiment was that if certain concentrations of ethanol are needed in order to kill bacteria, why was it that the cleaners still worked at half their normal concentrations? We thought that perhaps the ratio of bacteria to cleaner had some influence,

  2. The comparison of bacterial content in a range of milks.

    * Death phase-more bacterial cells are dying than are being produced, so the population declines. These bacteria are microscopic, therefore a single drop of cow's milk might contain up to 30 billion bacteria. Psychrophiles (micro-organisms which are able to multiply under cold conditions e.g.

  1. Mining for Gold and Copper using Biohydrometallurgy.

    The copper is removed by bonding to a ligand, which is a large molecule consisting of a number of smaller groups each possessing a lone pair. The ligand (L) is dissolved in an organic solvent such as kerosene and shaken with the solution producing this reaction: Cu2+(aq)

  2. Investigating the effect of four antibiotic agents on gram positive and gram negative bacteria.

    to the technique and then tried the same technique with the wire loop but had the petri dish upside down to reduce the risk of airborne contamination. Starting at one edge of the plate, I was taught to aim to cover the entire agar as if I was colouring in,

  1. Investigation - Examination of bacterial sensitivity on antibiotics.

    Use the sterilised forceps to pick the antibiotic disk. (x) Lift the lid of the inoculated petridish with Ecoli and place the antibiotic disk in the middle of the dish using the forceps. (xi) Pass the forceps through flame again before placing it back into the alcohol.

  2. Copper Extraction

    Fe(III) As(III) As(V) The overall reaction looks like this: 2FeAsS + 7O2 + 4H+ + 2H2O 2Fe3+ + 2H3AsO4 + 2HSO4- The remaining waste water is treated with either crushed limestone or hydrated calcium hydroxide to neutralise the sulphuric acid.

  1. Science Chemistry Casestudy

    protect plants or wood or other plant products from harmful organisms; to regulate the growth of plants; to give protection against harmful creatures; or to render such creatures harmless [1]. * Benefits of pesticides in crop production/yields There are various benefits when using pesticides in crop productions because it: -

  2. Method of extracting copper and gold by bacterial leaching.

    An electro-winning process is then carried out, whereby a current is run through the solution containing the Cu2+ ions, and pure copper atoms collect on the cathode?. The extraction process for gold is different, initially froth floatation occurs to separate the tailings from the tailings and bioleaching is then carried out on the slurry of concentrate.

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