Bioleaching currently accounts for an estimated 20 percent of the worlds mined copper, and is in use at about 20 mines around the world. Hedrich, sabrina some past projects include in situ mining, biodegradation, bioremediation, and bioleaching of ores. For separation of copper and tin, tin must exist as a solid in this region and can be removed by filtration. This consisted essentially in removing the precipitate formed when ammonia was added to the solution of the ash, and precipitating the copper in the filtrate with potassium ferrocyanide from an acid solution. Chalcocite cu 2 s is the main copper sulphide mineral mined at bioleaching operations. Demonstration of high temperature heap bioleaching of chalcopyrite copper ore it is a worldwide phenomenon that, as copper mines are getting deeper, more sulfidic ore is encountered. Pdf research progress in enhanced bioleaching of copper. Bacterial consortium for copper extraction from sulphide. The inductively coupled plasmaatomic emission spectroscopy icpaes is a very accurate way to analyze metals in solution. Extraction of tin and copper by acid leaching of pcbs amit chaurasia, k. Introduction, methods, application, copper, microorganisms, and processes. Copper nickel tubes are generally formed from strip and then custom installed as condenser. Demonstration of high temperature heap bioleaching of.
In recent years, a new discipline of mineral science namely biohydrometallurgy. Some of the chalcocite heap operations began as oxide chemical leach operations and were converted to bioleach oxidative operations by heap aeration andor inoculation. For example, sulfur is oxidized to sulfuric acid by thiobacillus liu et al. Bioleaching and phytomining extraction of copper prezi. While world demand for copper is growing, the minerals industry is increasingly faced with the need to process lowgrade ores, overburden and waste from current mining operations watling, 2006. This is a low technology process and renders low productivities and recoveries. An acidic solution containing bacteria is applied and allowed to percolate through the heap, draining into a collecting pool. Copperii oxide can be reduced by reaction with carbon some copper ores may contain only small amounts of copper. The copper rich solution is transferred to electro winning whilst the copper poor solution is refreshed with sulfuric acid and fed as barren solution again to the heap. Biotechnology is an area that has produced a considerable increase in recent years, mainly because occurrence of microbiological techniques and molecular biology, which help to isolate. The metals can be recovered by the microorganisms by two processes. The eph diagram for the coppernitratewater system, is shown in fig. Recovery of copper from oxide copper ore by flotation and leaching kiraz, emirhan m. Nonetheless, at the largest copper mine of the world, escondida in chile the process seems to be.
Soil microorganisms are very closely involved as catalytic agents in many geological processes. Natural bioleaching has been taking place for almost as long as the history of the world, but it is only in the last few decades that we have realized that bioleaching is responsible for acid production in some mining wastes, and that this bacterial activity can be used to liberate some metals. Bioleaching is the extraction of metals from their ores through the use of living organisms. A case study for kraku bugareskucementacija deposits eastern serbia grozdanka d. In 2008 the copper production will be close to 18 mt. Bioleaching is applied mainly for copper recovery from lowgrade sulfide ores via heap leaching. Kordosky synopsis the concept of selectively extracting copper from a lowgrade dump leach solution followed by stripping the copper into an acid solution from which electrowon copper cathodes could. Bioleaching of copper from chalcopyrite ore by fungi. The rio tinto mines in southwestern spain are usually considered the cradle of biohydrometallurgy. The most successful copper heap leaching operations have been those processing copper oxides and secondary copper sulphides.
Extraction of tin and copper by acid leaching of pcbs. Their flowsheet forthe treatment ofcopper zinc concentrates isshown infig. Copper has a ground state electronic configuration of 3d 10 4s 1 and occurs in the environment in three major valence states. Copper leaching throughout the world copper leaching plants have been widely used for many years. Phytoming and bioleaching extraction of copper from ores bioleaching advantages we can use waste ores, reducing the impact of mining on the environment. Several cobaltii, copperii and nickelii complexes of nicotinoylhydrazinederived compounds were prepared and characterised by physical, spectral and analytical data. Energy efficient, using almost half as much energy as traditional extraction. The bioleaching of sulphide minerals with emphasis on. Mankhand department of metallurgical engineering, indian institute of technology, bhu, varanasi, 221005, india.
These are called low grade ores and have less than 1% copper but they are still used because copper is so valuable. Copper extraction from the discarded printed circuit board. Corrosion control of copper in nitric acid solutions using. Nevertheless, dump bioleaching is economical, mainly because it recovers copper. Bioleaching of metal sulfides is caused by diverse groups of bacteria. If they are present in the ore, extra cyanide must be added which can add considerably to the cost of leaching the gold. Ayres et al the life cycle of copper, its coproducts and byproducts iv. Research strategy precipitation of copper onto sulfide minerals has been reported ahonen and tuovinen, 1994, but not to an extent sufficient to account for the copper recovery that was experienced in the test heap.
A as a method of the extraction of minerals, it was well established b as a method of the extraction of minerals well. Recent development has shown commercial application of the process and, concurrently, details pertaining to the key microorganisms involved in these processes have been described. Results of bioleaching of a complex copper leadzinc sulfide ore in presence of a. Biological role of cobaltii, copperii and nickelii.
Improvements in copper heap leaching by use of wetting agents. Other minerals, such as arsenic can react with the oxygen and slow the rate of gold dissolution. Ii 2 copper mine, smelter and refinery production in developing countries in. Application of bioleaching to copper mining in chile. It is incorporated into a variety of organics which perform specific metabolic functions.
Methods of metal recovery by microorganisms 2 methods. Table of contentsbringing copper metal into solutionrecovering copper metal from leach liquorscopper leaching equipmentcopper leaching costscopper leaching practices the advance made in recent times in this branch of metallurgy is indicated by the attention the subject is receiving from important american copper producing companies. Biomining is a process in which microbes such as bacteria, are used to speed up bioleaching, the process of breaking down the minerals surrounding metal ore. Thus the leach can be considered to be highly significant when compared to the content found in primary mineral sources. The multisulfide ore constituted of chalcopyrite, sphalerite, galena, and pyrite as the major minerals 8. Modelling copper heap leaching leaching implies a reaction between solid particles and a liquid phase. This is a foreshortened version of aes cyprium metal from cyprus.
Morenci western copper concentrate mineralogy ymixed chalcopyrite, covellite, chalcocite, pyrite medium temperature and direct electrowinning mtdew process selected ybest fit with morenci concentrate production and acid balance yutilize existing ew and sx capacity at morenci copper production capacity 75,000 tons per year. Bioleaching involves the use of microorganisms to catalyze the oxidation of iron sulfides to create ferric sulfate and sulfuric acid. Copper is required for the normal functioning of plants, animals and most microorganisms. The abundances of the elements in humans human abundance by weight. In order to improve copper leaching efficiency from the flexible printed circuit board pcb by acidithiobacillus ferrooxidans, it is necessary to quantitatively measure the bacteria bioleaching copper under extreme acidic condition from flexible pcb. Early application of bioleaching to copper mining centred in its recovery from dumps gentina and acevedo, 1985.
Bioleaching is a simple and effective technology for metal extraction from lowgrade ores. Bioleaching is one of several applications within biohydrometallurgy and several methods are used to recover copper, zinc, lead, arsenic, antimony, nickel, molybdenum, gold, silver, and cobalt. Acid heap leaching has been widely used to extract copper from. Extraction of copper copper is sometimes found as native metal copper ores include copperii oxide and copperii sulfide. Copper is number 29 in the periodic table of elements. The composition of bacterial populations in copper bioleaching systems was investigated by analysis of dna obtained either directly from ores or leaching solutions or after laboratory cultures. Pdf chile has a great tradition of producing and exporting copper. It is operated as simple heap leaching process or combination of both heap leaching and in situ leaching process. Introduction bioleaching is the simple and effective technology for metal extraction from low grade ores and mineral concentrate by the use of micro organisms.
As part of a broad mission to conduct research and provide. Bioleaching bioleaching is the extraction of metals from their. Copper content in the powder generated by the processing of pcbs from obsolete electronic devices is 17. Pdf the commercial application of copper bioleaching, an environmentally friendly approach for lowgrade and secondary mineral resources.
Pdf compared with the traditional pyrometallurgical process, copper bioleaching has distinctive advantages of high efficiency and lower cost, enabling. Leaching kinetics of copper from waste printed circuit boards by electrogenerated chlorine in hcl solution eunyoung kima, minseuk kimb, jaechun leeb. The copper book for architecture, is distributed in many countries. Bioleaching and biomining pdf microbial leaching bioleaching, biomining. The main copper processing route includes pyrometallurgy and the remaining copper slag from smelting may still contain copper in amounts found in the ore. Over the last several decades, it has become the first producer on an international. It finds application in the extraction of metals from their ores. Bioleaching has been discussed with copper, uranium, gold, silver and silica. Corrosion control of copper in nitric acid solutions using some amino acids a combined experimental and theoretical study k. Bioleaching of copper, nickel and cobalt from the low. Dilute sulphuric acid ph 2 is percolated down through the pile. Bioleaching is used today in commercial operations to process ores of copper, nickel, cobalt, zinc and uranium, whereas, biooxidation is used in gold processing and coal desulfurization. Excess copper inhibits plant growth and impairs important cellular processes i. Usually, bioleaching is referring to the conversion of solid metal values into their water soluble forms using microorgan isms.
This process was later on employed for recovering metals from ores containing low quantity of the metal. Leaching kinetics of copper from waste printed circuit. Bio leaching group members mehwish nazeer, kanza saleem, nazish mehmood m. It is the key component of redox enzymes and of haemocyanin.
This is much cleaner than the traditional heap leaching using cyanide. This is much cleaner than the traditional leaching processes like heap leaching using cyanide or other chemicals. Here bioleaching of copper slag material with a copper content of about 1 % grain size the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria taken an active part in the process. These include mineral formation, mineral degradation, sedimentation and geochemical cycling.
Bioleaching technology in minerals processing john neale mintek, biotechnology division private bag x3015, randburg, 2125, south africa bioleaching is a process that employs microorganisms to dissolve leach sulphide minerals. Because it is an essential metal, daily dietary requirements have been recommended by a number of agencies. Khaled electrochemistry research laboratory, chemistry department, faculty of education, ain shams university, roxy, cairo 11711, egypt. Copper is essential for all life, but only in small quantities. As a member of the 3d transition metal series, copper and six other metals in the serieschromium, iron, cobalt, manganese. In the human organism, copper exists in two forms the first and second oxidation form, as most of the copper. Copper is the oxidising agent it accepts electronsand iron is the reducing agent it loses electrons. Thebasicequations forthe dissolution reactions areasfollows.
Microbial leaching is the process by which metals are dissolved from ore bearing rocks using microorganisms. Furthermore, the average grade of reserves and unexploited deposits is dropping. These compounds and their complexes have proven to be antibacterial. Cartridge brass reflects the deep drawing characteristic of that alloy. Most of theunleached copper canbefloated from the residue and recycled. A woodcut from his book illustrates the manual transport of metalcontaining leachates from mines and their evaporation in the sunlight fig. Mesophiles moderately thermophilic bacteria extremophiles. In the case of copper, copper sulfide is microbially oxidized to copper sulfate and metal values are present in the aqueous phase. Nickel and cobalt recoveries at the initial ph of 1. Printed circuit board pcb waste is generally dumped as a landfilling or treated pyrometallurgically, which. Introduction copper cu is an essential trace element for humans and animals. Leaching process was first observed in pumps and pipelines installed in mine pits containing acid water. Copper recovery using leachsolvent extractionelectrowinning technology.
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