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... Around 96% of the global Mn production occurs in 12 countries, including China, followed by India, Ukraine, South Africa, Norway, and the Republic of Korea. The global utilization of Mn is beyond 1,400,000 tons, which is estimated to rise several folds in the coming years (Ghosh et al. 2016;) (Figure 1). The utilization of Mn ore has increased significantly in the recent times due to rising of steel manufacture over the years. ...
... The confirmation of the Mn reductase existence in the outer layer of oxygen, which is essential for Mn reduction through microbes, has been done through cell fractionations experiments as carried out by Ehrlich (1993). MnO 2 reduction through bacteria needs direct interaction with the metal surface (Ghosh et al. 2016Haghshenas et al.2007 In the matter of this indirect mechanism, there is no direct connection in between microbes and minerals. ...
... There are so many physical and chemical parameters, which influence the bioleaching process such as different types of microbes, types of waste residues, many physiochemical characteristics, and different operating systems (Ghosh et al. , 2016. The conventional leaching bacterium belongs to the genus Acidithiobacillus that are usually Gram-negative proteobacteria . ...
Research
Mineral resources have been counted as public assets with economic benefit since time immemor-ial. Due to the rising issue of decreasing mineral deposits, recovery of metals from several waste residues has become progressively more essential. Novel and efficient recycling processes have been on the rise globally. Manganese (Mn) as the fourth most industrially applicable metal generates an extensive quantity of metallic waste which not only leads to loss of precious metal but also results in environmental toxicity. Globally, around 7 million tons of high-grade ores are produced , whereas 8 million tons of Mn alloys are produced yearly. Therefore, it is of greater significance to recover and recycle Mn from various waste residues. Various physical and biological techniques have been developed for recycling Mn from waste residues. Traditional Mn extraction processes are costly and labor intensive in nature, on the contrary, bioleaching techniques using diverse microorganism's, form the basis of an efficient, eco-friendly, and economically sustainable process of metal recovery. The quick progress in current methodologies to counteract the fast consumption of innate mineral resources involves the proper utilization of unused waste residues containing industrially important metals like Mn. This review focuses to enumerate diverse features of Mn recovery, efficient methodologies, bioleaching of Mn, merits of Mn bioleaching, and applications of recycled Mn along with the futuristic applications. Manganese recovery by means of biol-eaching will play a major role in changing the present situation where innate assets are quickly diminishing and substitute for metal recovery methodologies are the demand of this time. ARTICLE HISTORY
... However, bacterial strains play a crucial role in Mn biogeochemical cycling due to the presence of inherent cellular mechanisms aiding in maintaining homeostasis across the ecosystem 5 . Microbial strains are known to possess enzymes like multi copper oxidase and manganese reductase 6 which can take up excess Mn from the environment and solubilise it in the cell before releasing it to the environment [7][8][9] . Some bacterial species such as Bacillus and Aerobacter, release strong chelating agents called "siderophores" into the surroundings which generally act as metal-capturing devise. ...
... In some cases, bacteria require direct contact with the ore constituents to solubilise the metals. Some strains also use enzymatic machinery to solubilise metals conjugated in the ore samples 8,30 . ...
... Enzymatic mechanisms in specific bacterial strains help them to scavenge this metal ion and associated elements, thereby playing a crucial role in biogeochemical cycles. Bacterial strains mostly carry out solubilisation through direct and enzymatic mechanism which involves direct contact of the ore surface with the bacteria and the enzymatic machinery within the bacterial strains 8,24 . Mn solubilising microbial strains are known to possess various metal solubilising enzymes like multi copper oxidase and manganese reductase (Fig. 14) 6,9 which can take up excess metal ions from the environment and solubilise it in the cell before releasing it to the environment 7,8,34,35 . ...
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To extend the knowledge on the microbial diversity of manganese rich environments, we performed a clone library based study using metagenomic approach. Pyrosequencing based analysis of 16S rRNA genes were carried out on an Illumina platform to gain insights into the bacterial community inhabiting in a manganese mining site and the taxonomic profiles were correlated with the inherent capacities of these strains to solubilise manganese. The application of shot gun sequencing in this study yielded results which revealed the highest prevalence of Proteobacteria (42.47%), followed by Actinobacteria (23.99%) in the area of study. Cluster of orthologous group (COG) functional category has 85,066 predicted functions. Out of which 11% are involved in metabolism of amino acid, 9% are involved in production and conversion of energy while Keto Encyclopedia of Gene and Genomes (KEGG) functional category has 107,388 predicted functions, out of which 55% are involved in cellular metabolism, 15% are environmental and information processing and 12% are genetic information processing in nature. The isolated microbial consortia demonstrated visible growth in presence of high concentrations of Mn. Solubilisation studies resulted in 86% of manganese recovery after 20 days. The result presented in this study has important implications in understanding the microbial diversity in manganese contaminated mine tailings and their role in natural geochemical cycling of Mn.
... The continuous loss of natural resources, increasing energy prices and tight environmental restrictions also lead to expanded metal recovery efforts (Ghosh et al., 2016;Shen et al., 2007;Xin et al., 2011). The development of a competent and cost-effective extractive method is now awaiting low-grade ores in millions of tons (Ghosh et al., 2016;Pradhan et al., 2006) (Arsent'ev et al., 1991). ...
... The continuous loss of natural resources, increasing energy prices and tight environmental restrictions also lead to expanded metal recovery efforts (Ghosh et al., 2016;Shen et al., 2007;Xin et al., 2011). The development of a competent and cost-effective extractive method is now awaiting low-grade ores in millions of tons (Ghosh et al., 2016;Pradhan et al., 2006) (Arsent'ev et al., 1991). High-grade manganese ore resources (>40%) are typically used to produce metallic alloys by pyrometallurgical processes as they are more readily available for this process (Aslan, 2007). ...
Article
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Using a software-based experiment design, the application of the leaching process for the extraction of manganese from Zinc Plant Slag (ZPS) was investigated. In this study, the effect of different parameters, i.e., H2SO4 concentration, pulp density, agitation rate, temperature and reaction time, was investigated. Response Surface Methodology (RSM) based on the Central Composite Design (CCD) has been implemented to consider the main parameters. A hydrometallurgical route to manganese silicate from spent zinc plant residue has been proposed in this investigation. Based on the investigation, Mn can be extracted from ZPS in sulfuric acid without any oxidant agents. The results showed that the optimum conditions of this study are an H2SO4 concentration of 2 mol/L and a solid/liquid ratio of 0.07 g/mL at 50°C for 150 min and an agitation speed of 1000 rpm. A manganese leaching efficiency higher than 83% is reached under these conditions, with a corresponding 22% iron, 23% lead, 68% zinc and 65% aluminum.
... Many studies have been conducted for recovery of manganese from EMS, including electrochemical (Shu et al., 2016b;Wang et al., 2016), concentrated acid extraction (Li et al., 2016b), ultrasonic extraction (Chandra et al., 2011), surfactant (Shu et al., 2020), water extraction (Ayala & Fernández, 2015;Zheng et al., 2020), and bio-leaching (Ghosh et al., 2016). Among those methods, the bio-leaching method has attracted more attentions due to its low energy consumption and low secondary pollution (Rao et al., 2010;Zhu et al., 2011). ...
... About 98% of Mn was extracted by Y1. The leaching efficiency of Mn from EMS was higher than the results of similar studies (Ghosh et al., 2016;Xin et al., 2011). ...
Article
The related microbial metabolomics on biological recovery of manganese (Mn) from Electrolytic Manganese Slag (EMS) has not been studied. This study aimed at open the door to the metabolic characteristics of microorganisms in leaching Mn from EMS by using waste molasses (WM) as carbon source. Results show Microbacterium trichothecenolyticum Y1 (Y1) could effectively leach Mn from EMS in combination with using waste molasses as carbon and energy sources. For the first time, Y1 was identified to be capable of generating and then metabolizing several organic acids or other organic matter (e.g., fumaric acid, succinic acid, malic acid, glyoxylic acid, 3-hydroxybutyric acid, glutaric acid, L(+)-tartaric acid, citric acid, tetrahydrofolic acid, and L-methionine). The production of organic acids by Y1 bacteria was promoted by EMS with the carbon source. This study demonstrated for the first time that metabolic characteristics and carbon source metabolic pathways of Y1 in bioleaching of Mn from EMS.
... This is due to the ability of manganese solubilization by microorganisms and also due to the influence of the transitional compounds formed during solubilization (Das et al. 2011;Chen et al. 2011). Researchers showed that it is possible to mobilize metals from mining wastes which will serve a dual purpose of both resource recycling and environmental beneficiation (Mohapatra et al. 2007;Das et al. 2012;Ghosh et al. 2016;Mishra et al. 2019). There are recent reports on manganese biosolubilization in diverse group of microorganisms including Lysinibacillus sp. ...
... Due to extensive mining, mining wastes in the form of low-grade ores are present in millions of tones in this region which could be used as an alternative source of Mn. Figure 1 depicts the satellite image of Barbil District of Odisha obtained from Google (Maphill). The collected ore was crushed, grounded, and sieved for leaching experiments as per the protocols of Ghosh et al. 2016. The ore was grinded by the ball mill and sieved to get different size fractions using sieves of diameter > 4 mm, 4-1 mm, 1 mm-150 μm, and < 150 μm. ...
Article
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There has been alarming depletion of manganese (Mn) reserves owing to the ongoing extensive mining operations for catering the massive industrial demand of this element. Moreover, the mining operations have been leading to the generation of Mn-rich waste, thereby contaminating both terrestrial and aquatic bodies. The current scenario necessitates the development of alternative processes for bioremediation as well as economic recovery of Mn from mining wastes. The present investigation aims to report the bioleaching of Mn by Lysinibacillus sp. from mining waste residues in the context of mine waste remediation. Results confirmed that the native isolate had a high Mn biosolubilization potential with a solubilizing efficiency of 84% at the end of a 21-day study under optimized conditions of pulp density 2% (< 150-μm particle size), pH 6.5, and temperature 30 °C. Fourier transform infrared spectroscopy (FTIR) studies followed by liquid chromatography mass spectrometry (LC-MS) analysis were used to ascertain the change in microbial protein conformation, configuration, and protein identification. The results revealed the expression of heat shock proteins (HSP) from the family HSP which is predominantly expressed in bacteria during stress conditions. This study represents the application of native bacterial strain in Mn biosolubilization. We foresee the utility of proteomics-based studies to provide a methodological framework to the underlying mechanism of metal solubilization, thereby facilitating the two-tier benefit of recovery of Mn from alternative sources as well as bioremediation of waste having high manganese content.
... Now, there have been reports on some representative processing methods, such as reduction roasting-ammonia leaching, 11 cuprous ion catalytic reduction-ammoniacal leaching, 12 reduction acid leaching in H 2 SO 4 or HCl system, 13,14 rusting-leaching process, 15 and bioleaching. 16 A critical review of the literature, especially in terms of energy consumption, carbon emission, and selective extraction, indicates that the reductive leaching of manganese nodules in the sulphuric acid system is a relatively promising and inexpensive approach. ...
Article
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The effect of Fe ³⁺ ions on the ocean manganese nodule reductive leaching in imitated sulphuric acid solutions was investigated.
... Marine pollution due to synthetic microfibers and other anthropogenic sources is a serious matter of concern and significant treatment technologies for the removal of these pollutants are of immense importance (Das and Mishra, 2008;Ghosh et al., 2016;Das and Mishra, 2010). Removal of microfibers from contaminated water sources using current technologies is prohibitively expensive due to high capital expenditure and operating expenses. ...
... Over the years, bioleaching technology, which has been applied to copper, uranium, coal, nickel, and manganese mining [41][42][43], has progressed considerably, especially in Chile, South Africa, the United States, Australia, India, Mexico, Iran, and China. In 1762, in the Rio Tinto Mine of Spain, Copper (Cu) was leached from pyrite mixed with copper by acid mine drainage (AMD). ...
Article
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The commercial application of copper bioleaching, an environmentally-friendly approach for low-grade and secondary mineral resources recycling, has increased worldwide since the 2000s. As the world's second-largest economic entity and the largest developing country, China has the largest demand for metal resources, significantly advancing the theory and industrial technology of copper bioleaching. This paper reviews the exploration and application of copper bioleaching in China. Two typical bioleaching applications and technological processes, bioheap leaching at the Zijinshan Copper Mine and bioheap leaching at the Dexing Copper Mine, are introduced. The considerable research completed by researchers is summarized, especially focusing on the isolation and identification of leaching bacteria, the bioleaching mechanism and interface reactions, multistage percolation behavior, bioleaching system reconstruction, the multiphysics coupled model, and enhanced copper bioleaching from waste printed circuit boards (WPCBs). Based on this investigation in China, key trends and prospects in copper bioleaching-such as efficiency improvement, environmental protection, and improved technology applications-are proposed.
... Bioreactor based bioleaching operations (Jungles et al. 2014;Zhou et al. 2009) such as compost bioreactors (Aerobic wetlands), stirred tank reactor (STR), continuous flow stirred tank reactors (CSTR), batch bioreactor for manganese recovery are presented in detail in the ( Table 3). The driving parameters of manganese biorecovery such as the biological factors, the microbial community involved and the diverse mechanism have been reviewed by Ghosh et al. (2016). Chemical solubilisation methods of Mn lead to the introduction of hazardous pollutants into the environment. ...
Article
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The global consumption of manganese is rising due to its growing industrial requirement while the natural reserves of manganese are diminishing at an alarming rate. Consequently, recovery of manganese from metal containing wastes has become highly crucial. Bioleaching of metal from wastes using microbes provides an adequate advantage over the traditional method of recovery. A molecular level understanding of microbial catalyzed manganese recovery is essential for the exploitation of novel microorganisms for similar applications. In current scenario, the application of bioleaching concentrates on cost effective and eco-friendly recovery of precious metals from mining and industrial wastes. This review encompasses the modern improvements in biomining, highlights the comprehensive factors that emphasize the selection of manganese recovery technique, shed insights into spectacular progress in developing molecular based technologies and also identifies the applicability of different models in metal bioremediation which will not only aid in pollution abatement but also in the prevention of occupational health disorder.
... Bioreactor based bioleaching operations (Jungles et al. 2014;Zhou et al. 2009) such as compost bioreactors (Aerobic wetlands), stirred tank reactor (STR), continuous flow stirred tank reactors (CSTR), batch bioreactor for manganese recovery are presented in detail in the ( Table 3). The driving parameters of manganese biorecovery such as the biological factors, the microbial community involved and the diverse mechanism have been reviewed by Ghosh et al. (2016). Chemical solubilisation methods of Mn lead to the introduction of hazardous pollutants into the environment. ...
... ferrooxidans) is by far the most widely used bioleaching microorganisms in ore leaching, including for Ni, Cu, Au, V, and Mn ores [7][8][9]. Additionally, a corrosion cell is the most common method in manganese oxide minerals and sulfide minerals for extracting valuable metals [10]. Many previous research studies have focused on the pyrite-pyrolusite coupled bio-leaching system. ...
Article
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Efficient extraction of Ni, Co, Cu, and Mn from low-grade and refractory ores is a common technical challenge. The present study proposes an Acidithiobacillus ferrooxidans-coupled leaching of Ni, Cu, Co, and Mn from oceanic polymetallic nodules and low-grade nickel sulfide ore, and focuses on the electrochemical behavior of the ores in simulated bio-leaching solutions. In the dissolution of polymetallic nodules, A. ferrooxidans facilitates the diffusion of H+ and accelerates electron transfer, producing a decrease in charge transfer resistance and promoting the Mn(IV)-preceding reaction. The use of A. ferrooxidans is beneficial for lower impedance of sulfur-nickel ore, faster diffusion rate of product layer, and better transformation of the Fe3+/Fe2+ couple and S0/S2− couple. A. ferrooxidans increases the potential difference between the nodule cathode and sulfide anode, and increases electron liberation from the sulfide ore. This motivates a significant increase in the average extraction rates of Ni, Co, Cu, and Mn in the bacterial solution. The bio-leaching efficiencies of Ni, Co, Cu, and Mn were as high as 95.4%, 97.8%, 92.2% and 97.3%, respectively, representing improvements of 17.1%, 11.5%, 14.3% and 12.9% relative to that of the germ- and Fe(III)-free acidic 9 K basic system.
... Marine pollution due to synthetic microfibers and other anthropogenic sources is a serious matter of concern and significant treatment technologies for the removal of these pollutants are of immense importance (Das and Mishra, 2008;Ghosh et al., 2016;Das and Mishra, 2010). Removal of microfibers from contaminated water sources using current technologies is prohibitively expensive due to high capital expenditure and operating expenses. ...
Article
Microfibers are emerging pollutants with widespread distribution in the environment and have adverse ecological impacts. Approximately 2 million tonnes of microfibers are released into the ocean every year from various sources, of which 700,000 micro fleeces are released from each garment through domestic laundry. Microfibers are the major marine pollutant throughout the world estimating 13 million tonnes of coastal synthetic fabric waste entering the ocean each year, out of which 2.5 million tonnes enter through adjoining rivers. It is anticipated that, to date, 1.5 million trillion of microfibers are present in the ocean. Microfibers are mistakenly ingested by marine animals and cause hazardous effects to aquatic species. Microfiber treatment techniques are under progress for efficient control of this pollutant. This article focuses on global microfiber generation and its sources, pathway of its entry into the environment and food chain, potential threat to aquatic animals and humans, present treatment technologies, and future challenges.
... The enzymatic reduction of manganese occurs in the form of respiration. In the direct mechanism, the bacteria uses MnO 2 as a final electron acceptor for cellular respiration instead of oxygen in an electron transport chain and causes the release of Mn 2þ into the medium (Ghosh et al., 2016). ...
Article
Spent coin cells are considered to be dangerous materials for the environment and human health due to their toxic compounds and their long half-lives. The present study investigated the bioleaching of lithium, cobalt, and manganese from spent coin cells using Acidithiobacillus ferrooxidans at different S/L ratios. It is shown that the S/L ratio of 40 g/L could be an optimal pulp density due to its high metal recovery and economic aspects. At an S/L ratio of 40 g/L, recovery rates of 100%, 88%, and 20% were achieved for lithium, cobalt, and manganese respectively. The results of structural analyses of the spent coin cells powder prior to and after bioleaching corroborated the bacterial activity effectiveness for metals mobilization from spent coin cells. The shrinking core model was employed to specify the rate-controlling step, which suggests that the diffusion of ferric ions plays a significant role in metals mobilization. A blank test was also performed and the results of it and bioleaching were compared; the results denoted the effectiveness of bioleaching.
... The other group of microorganisms, such as sulfur-oxidizing bacteria also has capabilities for extracting metals from their deposits. This group consists of the genus Acidithiobacillus, Acidiphilium, Acidiphilum, Sulfobacillus and Sulfolobus (Ghosh et al. 2016;Jang and Valix 2017;Jalali et al. 2019;Huynh et al. 2019;Retnaningrum and Wilopo 2019). Whereas, heterotrophic bacteria such as Leptospirillum ferriphilum, Pseudomonas sp., Bacillus sp., and Acinetobacter sp were also reported to be capable of solubilizing metals (Ghost and Das 2017;Thavamani et al. 2017;Wang et al. 2018;Dong et al. 2019;Saleh et al. 2019). ...
Article
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Prasidya DA, Wilopo W, Warmada IW, Retnaningrum E. 2019. Optimization of manganese bioleaching activity and molecular characterization of indigenous heterotrophic bacteria isolated from the sulfuric area. Biodiversitas 20: 1904-1909. The present research evaluated the manganese bioleaching potency of a heterotrophic bacteria KB3B1. This bacterial strain has been isolated from sulfuric area located at Ungaran, Middle of Java, Indonesia using modified 9K medium by adding of several organic nutrients. The manganese bioleaching activities of the strain was analysed by applying of varying glycine concentrations (0, 5, 10, 15 mg mL-1) with pyrolusite pulp densities of 0.02 g cm-3 on a rotary shaker at 180 rpm for 18 days incubation. Several parameters, including the growth of bacteria, pH values, the concentration of soluble manganese and cyanide, were investigated at the interval of 3 days. Molecular characteristics of the strain were further analyzed based on 16S rDNA gene sequences. After 15 days, the maximum yield of manganese 16.6% was achieved under the addition of 10 mg mL-1 glycine. This maximum extract obtained was followed by the maximum bacterial growth, pH, and cyanide product of the strain. Phylogenetic analysis showed that the strain was closely related with Bacillus niacini EP89. Besides, the average frequencies of guanine and cytosine (G+C) of the strain was in same range as that of the reference bacteria in the GenBank and Bergey's Manual Systematics of Bacteria.
... In recent years, for extracting that manganese metal from the ore, bioleaching is an innovative biological treatment to be applied in industrial scale. Compared to the traditional mining procedures, it does not need high energy and does not produce toxic pollutants [3][4][5][6][7]. The reserve of manganese metal located at Kliripan, Kulon Progo, Yogyakarta, Indonesia is found in its oxide form as pyrolusite. ...
Article
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The manganese bioleaching process of pyrolusite from Kliripan, Indonesia using Acidithiobacillus sp KL3 was investigated. The influence pulp densities of pyrolusite (0.01, 0.02, 0.03 and 0.05 g/cm3) on the bioleaching processes were studied for 16 days. The reduction on pH values, the increasing of oxidation-reduction potential (ORP), sulfate and manganese concentration were analyzed. The manganese bioleaching mechanism of pyrolusite by the strain was monitored using Scanning Electron Microscope-Energy Dispersive-X-ray Spectroscopy (SEM-EDX). The results indicated that 0.02 g/cm3 of pyrolusite was considered to be the optimal pulp density for manganese bioleaching process. During this process, pH values decreased, furthermore resulted in increasing of ORP, the concentration of sulfate and manganese. SEM-EDX analysis clearly showed the evidence of directly bacterial cell attachment into the surface of pyrolusite. Extracellular polymeric substances (EPSs) were further founded on that surface. Sulfur elemental was oxidized by the strain which was then confirmed of resulting in solubilized manganese.
... The inclusion of metal bioavailability as a freshwater quality component has been recommended in mining-impacted rivers as a more precise indication of mining pollution, preventing the underestimation of metal concentrations in pH-buffered rivers [56]. Moreover, besides the fact that pH and microbial enzymes influence metal solubility in freshwaters [57], the site-specific physicochemical environment (e.g., the presence of dissolved organic carbon or cationic stress) enhances the ecotoxicity of low zinc concentrations [55]. Metal phase distribution is also affected by pH variations, inducing metal precipitation or affinity to a matrix [56]. ...
Article
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Water quality assessments provide essential information for protecting aquatic habitats and stakeholders downstream of mining sites. Moreover, mining companies must comply with environmental quality standards and include public participation in water quality monitoring (WQM) practices. However, overarching challenges beyond corporate environmental responsibility are the scientific soundness, political relevance and harmonization of WQM practices. In this study, a mountainous watershed supporting large-scale gold mining in the headwaters, besides urban and agricultural landuses at lower altitudes, is assessed in the dry season. Conventional physicochemical and biological (Biological Monitoring Water Party-Colombia index) freshwater quality parameters were evaluated, including hydromorphological and land-use characteristics. According to the indicators used, water quality deterioration by mining was absent, in contrast to the effects of urban economic activities, hydromorphological alterations and (less important) agricultural pollutants. We argue that mining impacts are hardly captured due to the limited ecological knowledge of high-mountain freshwaters, including uncharacterized mining-specific bioindicators, environmental baselines and groundwater processes, as well as ecotoxicological and microbial freshwater quality components. Lessons for overcoming scientific and operational challenges are drawn from joint efforts among governments, academia and green economy competitiveness. Facing a rapid development of extractive industries, interinstitutional and multidisciplinary collaborations are urgently needed to implement more integrated freshwater quality indicators of complex mining impacts.
... Soil is the most fundamental resource of the terrestrial ecosystem which is facing strong pollution heaviness from different anthropogenic activities Mishra, 2008, 2010;Ghosh et al., 2016). Terrestrial environment is considered as the main source of this microfiber fiber pollution with over 400 Mts of plastic production globally each year (Qualman, 2017). ...
Article
The ever-increasing use of domestic washing machine by urban population is playing a major role in synthetic microfibers (SMFs) pollution via entering the ecosystem. Although many of the sources of fragmented plastic pollution in oceanic environments have been well known, urban areas are playing a major contributor due to huge populations. Thousands of scientific investigations are now reporting the adverse effect of these micro pollutants on aquatic and terrestrial environment, food chain and human health. Microfiber particles along with washing machine grey waters are emitted into urban drainage adjoining the lakes and river which ultimately mix in ocean water and after emission these tiny particles dispersed though out the ocean water by currents due to their low density. Environmental pollution cause by domestic laundering processes of synthetic clothes has been reported as the major cause of primary microplastics in the marine system. While community awareness and improved education will be successful in making public conscious of this problem, there needs to be more research on global scale to mitigate the ecological consequences of microfiber pollution by urban habitats through environmental friendly approach. This paper focuses to improve the understanding of urban population influence on microfiber pollution, their ecological toxicity to aquatic organism and humans, detection and characterization techniques with an emphasis on future research for prevention and control of microfiber pollution.
... The enzymatic reduction of manganese occurs in the form of respiration. In the direct mechanism, the bacteria uses MnO 2 as a final electron acceptor for cellular respiration instead of oxygen in an electron transport chain and causes the release of Mn 2þ into the medium (Ghosh et al., 2016). ...
... In this case, cell adhesion to the mineral surface is an absolute essential prerequisite. The indirect mechanism is mainly based on the production of metabolites like organic acid which in turn causes metal solubilization Das, Swain, Panda, Pradhan, & Sukla, 2012;Ghosh, Mohanty, Akcil, Sukla, & Das, 2016). ...
Article
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The rapid decrease of natural resources and generation of huge amount of metallic wastes from mining industries has led to the focus of researchers to shift to alternative methods of waste benefaction and resource recycling. This study aims at the development of an eco friendly technique to recover Manganese (Mn) from mining waste residues using Acinetobacter sp. Bioleaching experiments were conducted in shake flasks at initial pH 6.5, 5% w/v inoculums and 2% pulp density at 30 °C with agitation speed 200 RPM and Acinetobacter sp. as inoculum. Mn recovery of 76% was recorded in 20 days. The analysis of the changes in cellular protein expression and conformation was carried out through sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) and fourier transform infrared spectroscopy. The results reveal that bioleaching can alter protein expression and also result in conformational changes in protein structure. The present study sheds light on the greener alternative to recover and recycle manganese from wastes native bacteria. Exciting prospects for the utilization of mining wastes are in store in the near future; providing an economic and ecologically sound alternative to pyrometallurgical processes.
... The replacement of conventional processes, such as pyrometallurgy and hydrometallurgy, by large-scale environmentally friendly processes has been increasing Steinmann et al. 2014) worldwide, which is related to the concept of green chemistry (Brierley and Brierley 2001;Ghosh et al. 2016;Mani and Kumar 2014). An alternative is a biological process known as biomining, which is a generic term used to describe the extraction and recovery of metals presents in ores or wastes by biological systems (mostly prokaryotic microorganisms) (Johnson 2014). ...
Chapter
Mineral coal is one of the most employed natural resources that represent potential environmental issues. The mine tailing contains several valuable minerals such as zinc, molybdenum, vanadium, chromium, iron, and copper. Currently, the most part of mine tailings is disposed at large tailing ponds. Another important tailing from mineral coal is fly ash, the main residue from thermoelectric plants, which may also contain valuable minerals. Currently, the most part of coal fly ash produced is used as raw material for cement fabrication or disposed at ash ponds. In this sense, biomining and bioleaching is an economically and environmentally attractive technology that can be used for metal recovery from residues such as mine tailing and coal ash, in line up with the concept of green chemistry. There are sparse data available on bioleaching of coal ash using either autotrophic or heterotrophic microorganisms. Therefore, the aim of this chapter was to describe the key aspects related to biomining and bioleaching of mine tailing and coal ash, pointing out the state of the art and some future perspectives.
... Manganese is very used in the steel production (Ghosh et al. 2016), and the high concentration in this area can be related to the industrial activities nearby, as the biggest steel industry of Latin America is located at this region. Manganese is considered an essential micronutrient for the metabolic route in plants. ...
Article
In this study, we analyzed toxic metals in leaves and marine sediment samples from the black mangrove in Sepetiba Bay to measure contamination and the use of Avicennia schaueriana leaves as bioindicator of toxic metal environmental pollution. The concentrations of heavy metals, namely cadmium (Cd), chrome (Cr), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), molybdenum (Mo), and zinc (Zn), were determined by using inductively coupled plasma optical emission spectrometry (ICP-OES). High concentrations of Mn were found in the leaves, while high concentrations of Mo and Zn were found in sediments. A. schaueriana leaves showed a tremendous capacity to absorb toxic metals, tolerating high concentration of manganese and may be used as phytoremediator for this toxic metal in impacted coastal marine environments. Herein, we reported for the first time the utilization of Avicennia schaueriana as a highly efficient accumulator for Mn.
Article
The release of petroleum and petroleum derivatives, such as polycyclic aromatic hydrocarbons (PAHs), in the environment owing to anthropogenic activities, has become a major global threat to human health and ecological equilibrium. It causes a number of diseases and petroleum hydrocarbon (PH) compounds bind to soil components, making their removal very difficult. In order to find an eco-friendly, convenient, and non-expensive way, indigenous PH degrading microorganisms are employed. Biofilm, being a syntrophic association plays an important role in PAH degradation. The three-dimensional structure of the biofilm matrix is found to facilitate the efficient and rapid degradation of PAH. Various physicochemical parameters of biofilm are found to regulate the efficacy of PAH degradation. In order to amend certain drawbacks of biofilm mediated remedi-ation, these days microbial electrochemical systems are increasingly being used for redressal of PH contamination, where the solid anode functions as an endless electron acceptor and the microbial activity is stimulated by bio-current in situ to guarantee the PH removal from contaminated soil and water. Following uptake of emulsified PH, it may be denatured by biofilm-associated enzymes or by biosurfactant molecules (such as rhamnolipids). The biomolecules synthesized by the bacterial cells further help in the expression of the specific genes thereby helping in the enhancement of PH degradation. ARTICLE HISTORY
Chapter
A mature technology of lithium-ion batteries (LIBs) is applied in various electronic devices. The wide application of LIBs has brought large quantities of spent batteries, which has become a global problem. Owing to unfavorable effects of spent LIBs on the economic and environmental aspects, much effort has been made in many countries to manage and recycle the waste batteries. Owing to several restrictions in conventional recycling methods, the use of microorganisms has attracted increasing attention. The bio-hydrometallurgical approaches realize the win-win situation of environmental and economic benefits. In this chapter, the information available on the basic principles and recent developments of the bioleaching of metals from LIBs are reviewed in detail. Additionally, this chapter gives an overview of the previous studies performed in this field. Furthermore, the challenges, limitations, and potential solutions for applying more efficient bioleaching approach for recovery of metals from LIBs are highlighted.
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The study of the microbial ecology in extreme acidic environments has provided an important foundation for the development of mineral biotechnology. The present investigation reports the isolation, identification and molecular characterization of indigenous Manganese (Mn) solubilizing acidophilic bacterial strains from mine water samples from Odisha, India. Four morphologically distinct bacterial strains showing visible growth on Mn-supplemented plates of varying pH were isolated and identified. Mn solubilizing ability of the isolates was tested by growing them on Mn-supplemented agar plates. The appearance of lightening around the growing colonies of all the isolates demonstrated their Mn solubilizing ability in the medium. 16 S rRNA sequencing was carried out and the bacterial isolates were taxonomically classified as Enterobacter sp. AMSB1, Bacillus cereus AMSB3, Bacillus nealsonii AMSB4 and Staphylococcus hominis AMSB5. The evolutionary timeline was studied by constructing Neighbor-Joining phylogenetic trees. The ability of acidophilic microorganisms to solubilize heavy metals is supported by five basic mechanisms which include: enzymatic conversion, metal effluxing, reduction in sensitivity of cellular targets, intra- or extracellular sequestration, and permeability barrier exclusion. Such ecological studies undoubtedly will provide insights into Mn biogeochemical processes occurring in leaching environments. The application of acidophilic microbiology in mineral bio recovery and benefication has a large future potential.
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Chapter
This chapter discusses occurrence and mechanisms of microbial oxidation of Manganese. It examines the biogeochemistry and microbiology of manganese. The chapter focuses on two aspects of the field in which recent progress has been made: field studies of Mn(II) oxidation, including newly developed methods for measuring rates of Mn(II) oxidation and a (2) synopsis of some of the field data that unequivocally establishes the importance of microbes in Mn(II) oxidation in natural systems. The chapter also presents a brief synopsis of some of the field data that unequivocally establishes the importance of microbes in Mn(II) oxidation in natural systems. Finally, the chapter discusses the recent physiological, structural, and biochemical studies of microbial manganese oxidation. In this context, it presents an overview of the chemistry and biology of manganese, which must be understood in order to properly appreciates the field and laboratory studies.
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A combined novel process was developed to extract valuable metals from manganese–silver ore. The preferential dissolution of manganese from the primary materials was achieved through reductive leaching in dilute sulfuric acid medium with sodium sulfite as the reductant. Silver, which was enriched in the reductive leaching residue, was leached by complexation dissolution with hydrochloric acid and calcium chloride solution. Effects of process parameters on manganese extraction in the reductive leaching process were investigated, including the average particle size, the amount of sodium sulfite addition, sulfuric acid addition, liquid/solid ratio, leaching temperature and time. As for the silver extraction, the effects of Cl− concentration, hydrochloric acid addition, leaching temperature and time were also addressed. The results suggested that the extraction of manganese and silver could reach 99% and 92% respectively at the optimum conditions, while the high silica-containing product was obtained as the final residue.
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The contamination of aquatic sediments with metals is a widespread environmental problem. Coastal aquatic ecosystems with low hydrodynamics need to be periodically dredged in order to maintain the navigation depth and facilitate sailing; consequently large volumes of contaminated sediments need to be managed. Conventional remediation strategies include in-place sediment remediation strategies (e.g. in situ-capping) and relocation actions; in particular, landfill disposal and dumping at sea are still widely applied. Both this options are becoming unsustainable, due to problems associated with contaminant transport pathways, the uncertainties about long-term stability under various environmental conditions, the limited space capacity, costs and environmental compatibility. Alternative approaches have received increased attention; treatment and reuse of contaminated sediments is politically encouraged, but its application is still very limited. Because of the potential human health and environmental impacts of contaminated sediment, different chemical treatments are conventionally applied for contaminated sediments before reuse in other environmental settings. Environmentally friendly techniques developed for soils and other environmental matrices have been investigated for applications with sediments. Biotechnological approaches are gaining increasing prominence in this field and they are often considered as a promising strategy for the eventual treatment of contaminated sediments. In this paper an overview of the main treatment strategies potentially available for sediment contaminated with metals is given, together with a brief overview of the issue associated with the problem of the sediment management.
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Lateritic nickel ore from the Sukinda Mines, Orissa, India, was leached using Thiobacillus ferrooxidans, Bacillus circulans, Bacillus licheniformis and Aspergillus niger at 5% (w/v) solid: liquid ratio for 5-20 days. Maximum leaching of Ni was achieved with B. circulans (85%) and Aspergillus niger (92%) after 20 days. Bacillus circulans showed significantly higher rate of leaching than the other organisms giving 80% Ni extraction after 15 days. The importance and usefulness of heterotrophic organisms in metal extraction are discussed.
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In this research, the bioleaching mechanism of zinc and lead from high-grade Zn–Pb ore has been investigated. It is done by using mixed culture of iron and sulfur oxidizing moderate thermophilic bacteria at 45 C. Pulp density, initial pH and ferrous concentration were studied as influential parameters in bioleaching experiments. The optimum conditions were achieved at pulp density = 50 (g/L), initial pH = 1 and FeSO4.7H2O concentration = 75 (g/L) with 98.5% zinc recovery after 25 days treatment. Generally, an increase in ferrous concentration caused an improve zinc recovery, and an increase in initial pH and pulp density caused reduction in zinc recovery. However, in the test with optimum condition the lead dissolution was just 0.027% due to the lower Pb solubility. Furthermore, cadmium dissolution was 98% under optimum condition and results showed the cadmium dissolution was in direct proportion with zinc dissolution. Finally, 7.82% of arsenic and 8.52% of antimony dissolved during zinc bioleaching after 25 days treatment, both under above mentioned optimum condition.
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One hundred and five strains isolated from aquifer sediments andEscherichia coli ML30S were tested for their ability to reduce manganese oxides. Eighty-two strains, includingE. coli, reduced manganese. In most cases the bacterial activity decreased the pH and Eh below 6.75 and 350 mV, respectively, enhancing a spontaneous and nonspecific reduction of manganese. However, for 12 strains the reduction was specifically catalyzed by bacteria; the high pH and Eh values would not permit a spontaneous reduction of manganese. Some of the most active strains were identified as genera common in soils and waters, i.e.,Pseudomonas, Bacillus, Corynebacterium, andAcinetobacter. Two strains were studied in detail. One of the strains, identified asPseudomonas fluorescens, required contact between the cells and the manganese oxides for reduction to occur. The reduction was inhibited by 15 mM of sodium azide. The other strain, identified asAcinetobacter johnsonii, catalyzed manganese reduction by an inductive and dialyzable substance which was excreted by the bacteria. The mechanism involved has not been previously demonstrated.
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Laccases (benzenediol: oxygen oxidoreductase; EC 1.10.3.2), a multicopper oxidase enzyme, widely distributed in plants, fungi and bacteria have ability to catalyze oxidation of various phenolic and non-phenolic compounds as well as many environmental pollutants. The diversified functions of laccases, including the antagonistic ones such as their involvement in lignin biosynthesis (in plants) as well as lignin degradation (in fungi and bacteria), make them an interesting enzyme for study from the point of view of their structure, function and application. Important applications of laccases include delignification, pulp bleaching and bioremediation. The ability of laccases to polymerize natural phenols helps to develop new cosmetic pigments, hair dyeing materials, deodorants, toothpastes, mouthwashes and other useful products.
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A lab-scale circulation process of electrolytic manganese production with low-grade pyrolusite leaching by SO2 was introduced, exploring its feasibility and stability. Material balances of manganese and sulfur in circulation process were investigated. Results showed that the circulation process was entirely feasible. SO2 absorption efficiency of 99.66% and Mn extraction rate of 95.5% were obtained when a two-stage continuous countercurrent leaching process was used. The electrolytic manganese, meeting the needs of national industry grade standards, could be produced using purified leaching solution. 32 days' continuous running test proved good stability of the circulation process with the current efficiency of 78.1%, electricity consumption of 5396 kW h/t and total Mn recovery rate of 81.77%. The circulation process realized that the electrolytic manganese production with low-grade pyrolusite, has a wide prospect in industrial applications due to the advantages of stable performance, high efficiency and low consumption.
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Pressure leaching of manganese smelter dust with air as pressurized gas in a sulfuric acid medium was investigated. Optimum operating parameters were established as follows: liquid-to-solid ratio (mL/g), 5:1; initial sulfuric acid concentration, 120 g/L; leaching temperature, 120 °C; air pressure, 0.8 MPa; ore ratio (manganese smelter dust amount/pyrite amount), 1:0.5; leaching time, 2 h; and agitation speed, 500 r/min. Extraction rates of manganese and iron were obtained at 96.1% and 7%, respectively, under these conditions; and residual percentage of final acid was about 34.9%. Manganese can be effectively separated from impurities, such as iron, through leaching process. Leaching efficiency of manganese increased from 72.9% to 96.1%, whereas that of iron and the residual percentage of final acid both decreased with increase in leaching time from 40 min to 120 min. Pyrite was coated by elemental sulfur when temperature was higher than 119 °C, resulting in its inability to act as a reductant and to react with manganese dioxide. Therefore, leaching temperature must be lower than 120 °C. Pressure leaching technique for manganese smelter dust was proven to be effective and reliable.
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Based on the novel technology of Co-recovery of manganese from low-grade pyrolusite and vanadium from stone coal using fluidized roasting coupling technology, the leaching effect of manganese and vanadium has been investigated and many technical conditions have also been optimized. The results indicated that the optimum leaching efficiency of 99.25% for manganese and 91.84% for vanadium could be attained under the conditions that the mass ratio of stone coal to pyrolusite was 3:1, the roasting temperature of stone coal was 1000 °C, the roasting temperature of pyrolusite was 800 °C, the roasting time was 2 h, the sulphuric acid concentration was 2 mol/L, the leaching temperature was 75 °C, and the leaching time was 2 h.
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The active seafloor hydrothermal system at Guaymas Basin in the Gulf of California is unique in that spreading centers are covered with thick sediments, and hydrothermal fluids are injected into a semi-enclosed basin. This hydrothermal activity is the source of a large input of dissolved manganese [Mn(II)] into Guaymas Basin, and the presence of a large standing stock of particulate manganese in this basin has been taken as evidence for a short residence time of dissolved Mn(II) with respect to oxidation, suggestive of bacterial catalysis. During a recent Atlantis/Alvin expedition (R/V Atlantis Cruise #7, Leg 11, Jim Cowen Chief Scientist), large amounts of particulate manganese oxides were again observed in Guaymas Basin hydrothermal plumes. The goal of the work presented here was to identify bacteria involved in the oxidation of Mn(II) in Guaymas Basin, and to determine what molecular mechanisms drive this process. Culture-based methods were employed to isolate Mn(II)-oxidizing bacteria from Guaymas Basin hydrothermal fluids, sediments, and plumes, and numerous Mn(II)-oxidizing bacteria were identified based on the formation of orange, brown, or black manganese oxides on bacterial colonies on agar plates. The Mn(II)-oxidizing bacteria were able to grow at temperatures from 12 to 50°C, and a selection of the isolates were chosen for phylogenetic (16S rRNA genes) and microscopic characterization. Endospore-forming Bacillus species accounted for many of the Mn(II)-oxidizing isolates obtained from both hydrothermal sediments and plumes, while members of the alpha- and gamma-proteobacteria were also found. Mn(II)-oxidizing enzymes from previously characterized Bacillus spores are known to be active at temperatures greater than 50°C. The presence of Mn(II)-oxidizing spores - some of which are capable of growing at elevated temperatures - in hydrothermal fluids and sediments at Guaymas Basin suggests that Mn(II) oxidation may be occurring immediately or very soon after hydrothermal fluids emerge from the seafloor.
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Metal-oxidizing bacteria may play a key role in the submarine weathering of volcanic rocks and the formation of ferromanganese crusts. Putative fossil microbes encrusted in Mn oxide phases are commonly observed on volcanic glasses recovered from the deep ocean; however, no known Mn(II)-oxidizing bacteria have been directly identified or cultured from natural weathered basalts. To isolate epilithic Mn(II) oxidizing bacteria, we collected young, oxidized pillow basalts from the cold, outer portions of Loihi Seamount, and from nearby exposures of pillow basalts at South Point and Kealakekua Bay, HI. SEM imaging, EDS spectra and X-ray absorption spectroscopy data show that microbial biofilms and associated Mn oxides were abundant on the basalt surfaces. Using a series of seawater-based media that range from highly oligotrophic to organic-rich, we have obtained 26 mesophilic, heterotrophic Mn(II)-oxidizing isolates dominated by α- and γ-Proteobacteria, such as Sulfitobacter, Methylarcula and Pseudoalteromonas spp. Additional isolates include Microbulbifer, Alteromonas, Marinobacter, and Halomonas spp. None of the isolates, nor their closest relatives, were previously recognized as Mn(II) oxidizing bacteria. The physiological function of Mn(II) oxidation is clearly spread amongst many phylogenetically diverse organisms colonizing basalt surfaces. Our findings support a biological catalysis of Mn(II) oxidation during basalt-weathering, and suggest heterotrophic Mn(II) oxidizing bacteria may be ubiquitously associated with submarine glasses within epilithic and endolithic biofilms.
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Manganese‐oxidizing microorganisms have been implicated in the deposition of manganese in dark manganiferric rock varnish coatings on desert rocks. For this study, a collection of bacteria able to oxidize manganese has been obtained from rock varnish samples from the Sonoran and Mojave Deserts. Two groups of organisms predominated among the isolates. One group was identified as Arthrobacter spp. based on their rod‐coccus transformations, cell shapes, postfission division stages, and physiological characteristics. Another major group consisted of gram‐positive cocci tentatively ascribed to the genus Micrococcus. In addition, single isolates of Bacillus sp., Planococcus sp., Streptococcus sp., and Hyphomonas sp. were identified as manganese‐oxidizing bacteria. Some isolates grew too poorly to be easily characterized and identified.
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Previous studies identifying Fe3+ as the main oxidizing agent in CuFeS2 bioleaching suggests that if the precipitation of additional Fe3+ could be prevented, the Cu extraction yields should be enhanced. In this respect, the acid-generating nature of the biologically mediated oxidation of additional S0 to H2SO4 should theoretically serve as a pH regulator as well as biomass generator. This should prevent the precipitation of Fe3+ and attenuate the biomass reduction caused by the inhibitory effect of high Fe3+ concentrations. To prove the former hypothesis, three thermophile strains were employed for bioleaching of chalcopyrite under various additional S0 and Fe3+ concentrations. The hypotheses about additional S0 application were fully confirmed; the addition of S0 alone enhanced the leaching rates with A. brierleyi and M. sedula in media at initial pH 2. Although higher initial leaching rates were obtained with additional Fe3+, its role as the main leaching factor is questioned; leaching with thermophiles appears to depend on the availability of protons and ORP rather than on the prevention of Fe3+ precipitation. Additional S0 in media with high Fe3+ concentrations has shown the best improvements in the case of bioleaching with A. brierleyi, whereas improvements in bioleaching with M. sedula and S. metallicus were less notable.
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Cells of a soil Arthrobacter sp., and the manganese oxide they formed rapidly adsorbed manganous ions (Mn2+) from aqueous solutions. These ions could be desorbed by copper ions. There was no evidence that the adsorbed manganous ions were rapidly oxidized by non biological reactions. In gently stirred mixtures of cells and manganous ions the maximum rate of oxidation occurred at pH 6.5. The rate was very sensitive to small changes in pH below about pH 5.7 and above about pH 7.5. No oxidation occurred at pH 5.4 or at pH 7.9. Manganous ion concentrations between 0.5 mM and 6 mM had little effect on the maximum rate of oxidation. Higher concentrations became progressively inhibitory and 40 mM was completely inhibitory. The concentration for half the maximum rate was about 0.1 mM. Within limits the rate of oxidation increased in direct proportion to the numbers of bacteria in suspension. In deep vessels, static suspensions of the bacteria reduced bacterial manganese oxide and the rate of reduction was increased greatly by small additions of methylene blue. Methylene blue also partially inhibited the oxidation of manganese by cell suspensions in shallow vessels. These results are discussed in relation to manganese transformations in soil.
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The leaching of copper, nickel and cobalt from polymetallic manganese nodules from the Indian Ocean was investigated using a fungus — Aspergillus niger. Parameters such as initial pH, pulp density, particle size and duration of leaching were optimized for the bio-recovery of metals. At an initial pH of 4.5, 35ºC temperature and 5% (w/v) pulp density, about 97% Cu, 98% Ni, 86% Co, 91% Mn and 36% Fe were dissolved in 30days time using adapted fungus — as against only 4.9% Cu, 8.2% Ni, 27% Co, 6.3% Mn and 7.1% Fe solubilized in control experiment. The results indicate that A. niger released organic acids such as oxalic and citric acids which in turn reduced the host metal oxides/hydroxides to their lower valence states, and thus dissolving the base metals following the indirect mechanism. A comparison of results obtained with chemical leaching of sea nodules using citric and oxalic acids and bio-leaching using A. niger show that the leaching of metals was more effective in presence of the fungus. The appearance of some lower oxide phases of manganese and iron in the leach residue identified by XRD phase analyses may account for unlocking of the host lattice leading to release and dissolution of metals during leaching.
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Extraction of manganese from manganese dioxide ores was investigated using corncob as a reducing agent in dilute sulfuric acid medium. The effects of corncob amount, concentration of sulfuric acid, leaching temperature, reaction time and ore particle size were discussed. The leaching efficiency of manganese reached 92.8% while iron dissolved was 24.6% under the optimal condition which was determined for 10g of manganese dioxide ore as corncob amount of 3g, ore size of 75μm, sulfuric acid concentration of 1.9mol/L, leaching temperature of 85°C for 60min. In a word, the method provided a good leaching yield while making a productive use of corncob.
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