This document summarizes the process of bioleaching, which uses microorganisms to extract metals like copper, gold, iron, and uranium from ores. It discusses how different bacteria are used to oxidize the metal sulfides in ores, making the metals soluble and able to be extracted. The main methods used are heap leaching and in-situ leaching. Bioleaching has advantages of being low-cost and able to process low-grade ores, but is also time-consuming. Specific examples of how bacteria aid in leaching copper, iron, gold, and uranium are also provided.
“Bioleaching" or "bio-oxidation" employs the use of naturally occurring bacteria, harmless to both humans and the environment, to extract of metals from their ores.
Conversion of insoluble metal sulfides into water-soluble metal sulfates.
It is mainly used to recover certain metals from sulfide ores. This is much cleaner than the traditional leaching.
Bioremediation of heavy metals pollution by Udaykumar Pankajkumar BhanushaliUdayBhanushali111
Mechanisms and techniques used for Bioremediation which includes phytoremediation, Bacterial & fungal bioremediation. Examples of heavy metal pollution
“Bioleaching" or "bio-oxidation" employs the use of naturally occurring bacteria, harmless to both humans and the environment, to extract of metals from their ores.
Conversion of insoluble metal sulfides into water-soluble metal sulfates.
It is mainly used to recover certain metals from sulfide ores. This is much cleaner than the traditional leaching.
Bioremediation of heavy metals pollution by Udaykumar Pankajkumar BhanushaliUdayBhanushali111
Mechanisms and techniques used for Bioremediation which includes phytoremediation, Bacterial & fungal bioremediation. Examples of heavy metal pollution
Bioleaching, or microbial ore leaching, is a process used to extract metals from their ores using bacterial micro-organisms.
The bacteria feed on nutrients in the minerals, causing the metal to separate from its ore.
"Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater.
Bioremediation means to use a biological remedy to abate or clean up contamination.
According to the EPA, bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances”.
Bioleaching, or microbial ore leaching, is a process used to extract metals from their ores using bacterial micro-organisms.
The bacteria feed on nutrients in the minerals, causing the metal to separate from its ore.
"Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater.
Bioremediation means to use a biological remedy to abate or clean up contamination.
According to the EPA, bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances”.
Bioleaching,
Microorganinsms used in bioleaching,
Direct bioleaching, indirect bioleaching , bioleaching of gold, bioleaching of copper, bioleaching of uranium, factor affecting bioleaching, advantage of bioleaching, disadvantages of bioleaching, bioleaching summary
ENRICHMENT OF ORES BY MICROORGANISMS- Bioaccumulation and biomineralizationSijo A
Microbial ore leaching (bioleaching) is the process of extracting metals from ores with the use of microorganisms. This method is used to recover many different precious metals like copper, lead, zinc, gold, silver, and nickel. Microorganisms are used because they can:
lower the production costs.
cause less environmental pollution in comparison to the traditional leaching methods.
very efficiently extract metals when their concentration in the ore is low.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
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Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
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http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
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An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
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The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
1. BIOLEACHING OF IRON ,
COPPER, GOLD, URANIUM
PRESENTED BY:
Mousami Jaria
St. Geeorge College of Management
and Science
MSc Microbiology
Semester 2
2. BIOLEACHING
• It is the extraction of metal from sulfide ores or
concentrates using materials found native to the
environment namely water, air, microorganisms.
• It is the leaching of sulfide minerals that
distinguishes bioleaching from conventional acid
leaching wherein only oxidized minerals are
leached.
• Biooxidation is an associated process,it is the
oxidation of sulfide minerals associated with but
not necessarily part of the mineral to be
extracted.
3. • Bioleaching is used to process ores of copper,
nickel, cobalt, zinc, uranoum whereas
biooxidation is used in gold processing .
• Widely used in countries like Australia,
Canada, Chile, China, Indonesia,US, Zambia.
• Started around 1940s.
5. MICROORGANISMS INVOLVED
• The commonly used microorganisms in
bioleaching are:
o Thiobacillus thiooxidans
o Thiobacillus ferrooxxidans
• FUNGI:
Aspergillus niger, Penicillium simplicissimum
• Others involved are : Bacillus licheniformis,
B. luteus, Pseudomonas fluorescence, Sulfolobus
acidocaldarius etc.
7. MECHANISM
1. DIRECT BIOLEACHING:
• In this bioleaching , bacteria directly oxidize
minerals and solubilize metals.
• A physical contact exists between bacteria
and ores and oxidation of minerals takes
place through enzymatically catalysed steps
• Eg: pyrite oxidised to ferric sulphate
2FeS2 +7O2 2FeSO4 + 2H2SO4
8. 2. INDIRECT BIOLEACHING:
• In this type , bacteria produces the strong
oxidizing agent such as ferric ion and sulphuric
acid on oxidation of soluble iron or soluble
sulfur respectively.
• Acidic environment is absolutely essential in
order to keep ferric iron and other metals in
solution.
• Acidic environment is maintained by oxidation
of iron, sulfur, metal sufides or by dissolution of
carbonate ions
• Eg: bioleaching of uranium
UO2+ Fe(SO4) UO2SO4+2FeSO4
9. COMMERCIAL BIOMINING PROCESS
1. SLOPE LEACHING:
• Fine ore is kept in large slope shaped dump.
• A water solution made of inoculum is
continuously sprayed over the ore.
• After that , the leach liquor is gathered at
the bottom and processed for supplemental
metal recovery.
10. 2. HEAP LEACHING:
• The ore is arranged in large heaps .
• An aqueous mixture of microorganisms is
sprinkled over the leach pile.
• Then solution is collected to help recover
even more metal.
3. IN–SITU LEACHING:
• Ore remains in natural state while leaching
process takes place.
11. • Water that contain Thiobacillus is pushed
through drilled passageways within the ore
• The leach fluid is then stored untill its time for
metal recovery.
12. ADVANTAGES
• Simple
• Inexpensive
• Recovery of metals from low grade ore
• To extract expensive metals.
• Ideal for low grade sulfide ores.
• Environment friendly process.
• Employed for collecting metals from waste
and drainages.
13. DISADVANTAGES
• Low yield of minerals
• Time consuming ,6-24 months or longer.
• Requires large open area for treatment.
• Heat generated from dissolving process can
kill bacteria.
• High risk of contamination.
14. BIOLEACHING OF COPPER
• Chalcopyrite(CuFeS2), Covellite (CuS),
Chalcolite(Cu2S) are ores of copper from which
copper is recovered.
• Carried out by heap leaching or Insitu leaching.
• Action of acidithiobacillus involves the oxidation
of CuFeS2.
CuFeS2 + 4O2 Cu2 + Fe2 + 2SO42-
• Sulphuric acid is the byproduct of this reaction . It
maintains necessary acidic environment for
extraction.
15.
16. BIOLEACHING OF IRON
• Iron ores: Hematite(FeO3), Magnetite(Fe3O4),
Limonite(2FeO3.3H2O), Siderite(FeCO3).
• The oxygen must be removed from the iron
(Fe3) oxide in order to leave the iron behind.
• Acidithiobacillus ferrooxidans are used as
bacterial agents.
• Maximum extraction occurs at pH 1.3
Fe2O3+3CO 2Fe+3CO2
17. BIOLEACHING OF GOLD
• Gold ores: Calaverite ( AuTe2),
Sylvanite(Ag.Au)Te2, Petzite ( Ag3AuTe2).
• Gold cannot be extracted from low grade
sulfide ores.
• Iron and Sulfur acidophillic bacteria are able
to oxidize certain sulphidic ores. Thiobacillus
ferrooxidans is used in process
• Gold ore is first pretreated by roasting or
pressure oxidation.
19. BIOLEACHING OF URANIUM
• Uranium ores : Uraninite or Pitchblende (UO2),
Brannerite(UTi2O6).
• Uranium ores occur in low grade ores and is
insoluble, converted to leachable form by
oxidation of ferric ion.
• Insitu bioleaching technique used.
UO2+Fe(SO4)3 UO2SO4+2FeSO4
• In this process T. ferroxidants acts on iron
oxidant and not directly on uranium.
20. • It acts on pyrite (FeS2) in uranium ore and
produces ferric sulphate and sulphuric acid
• The soluble form of uranium is in leach liquor
is extracted in organic solvents like trimethyl
phosphate, precipitated and recovered.
