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Metal Mobilisation from Obsolete PCB of Mobile Phones Using Chemolithotrophs

Sonawane Pooja M., Gupta Shantikumar G.

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 6

79--84

EN

Tech is ubiquitous and a major mushrooming stream of hazardous material into the environment produced from the obsolescence of electronic equipment. The successful commercial operations of bioleaching processes from ores are now finding urban mines to be its potential source of base metals and precious metals. Among the six categories of e-waste, mobile phones pose a significant challenge due to technological upgradation and short life span of these gadgets. Thus, this study was precisely projected towards the e-waste generated by mobile phones. The ICP-OES analysis of 0.5 mm particle size of e-waste revealed the presence of base metals Co < Mg < Pb < Zn < Ni < Al < Cu and precious metals Pt < Au. The analysis showed that among base metals Cu is present in the highest concentration i.e., 244.303 g/kg and gold is present in 1106.6 mg/kg. In the current study, the plausibility of bioleaching processes using chemolithotrophs (Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans) for mobilisation of the metals from e-waste was investigated at variable pulp densities (0.5%, 1%, 1.5% and 2%). The results from the study indicated that the pure cultures of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were able to abundantly leach out base and precious metals at 0.5% and 1% pulp densities of powdered e-waste. At 1% pulp density, Acidithiobacillus ferrooxidans leached 79% of Cu and at 0.5% Ni and Al were leached in 80% and 70% respectively. Acidithiobacillus thiooxidans at 0.5% pulp density leached out Co, Zn and Pb in 61.7%, 60.9%, and 49.8% respectively. Among precious metals at 1% pulp density Acidithiobacillus ferrooxidans leached out Au in 55% and Acidithiobacillus thiooxidans in 67%. These findings highlight the potential application of biomining for mobilization and extraction of metals from electronic waste.

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Wykorzystanie mikroorganizmów i roślin do pozyskiwania metali

Gałuszka A.

Przegląd Geologiczny

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2005

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Vol. 53, nr 10/1

858-862

EN

Technologies using living organisms for extracting metals from mine wastes, ore concentrates and poor quality ores have been developed since the early 1980s. Of these technologies, the most popular is biomining that uses the natural ability of microorganisms to leach metals. Microorganisms oxidize sulfur and iron in sulfide ores, thus contributing to the conversion of insoluble metal sulfides to soluble sulfates, which enables to recover pure metals from extracts. By degrading the mineral (rock) matrix, microorganisms make extraction of precious metals with traditional techniques easier and more effective. Phytominig is based on the tendency of some plant species to bioaccumulate excessive amounts of metals from their hostrock. The plants, called hyperaccumulators are grown on highly mineralized soils or post-mine lands and their yield (bio-ore) is used as a pure metal source. Compared to the biomining, this technology is not so popular primarily because of the longevity of this process and its unprofitability. This report describes bio- and phytomining technologies, the most important species and their ecological demands, as well as biochemical processes that are associated with bio- and phytomining. The advantages and disadvantages of these technologies, and their potential for future applications are summarized in the last chapter.

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Bioleaching of cobalt from mineral products

Uryga A., Sadowski Z., Grotowski A.

Physicochemical Problems of Mineral Processing

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2004

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Vol. 38

291-299

EN

A kinetic approach to study cobalt, copper and arsenic bioleaching has been proposed and discussed. Two flotation by-products from the Lubin mine have been used. Acidithiobacillus ferrooxidans bacteria isolated from water from the “colour” lakes of Boguszow (Lower Silesia), was adopted to metal leaching. Semi-empirical model has been proposed to describe the metal extraction from collected samples. This model originated from the shrinking core and it was able to fit the experimental data. This model is an useful tool to investigate and compare ore bioleaching process for different size fractions.

PL

Badania kinetyki procesu bioługowania kobaltu, miedzi i arsenu zostały przeprowadzone w warunkach laboratoryjnych. Do badań użyto dwa półprodukty otrzymane z procesu flotacji z ZWR Lubin. Bakterie Acidithiobacillus ferrooxidans, które zostały wykorzystane w tych badaniach, były wyizolowane z kwaśnych wód pobranych z “kolorowych” jeziorek w okolicy Boguszowa (Dolny Śląsk). Do opisu procesu ekstrakcji badanych próbek został zastosowany półempiryczny model. Model ten zakłada istnienie warstwy półprzepuszczalnej nad ługowaną powierzchnią mineralną. Zastosowanie tego modelu okazało się odpowiednie dla opisu procesu bioługowania ziaren o różnych wymiarach.