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PL
Procesu bioutleniania odpadów arsenowych przeprowadzono w biorotorze i w kolbach Erlenmayera z wykorzystaniem bakterii Thiobacillus ferrooxidans. Kinetykę procesu opisano za pomocą równania logistycznego.
EN
The kinetics of bacterial oxidation of arsenic bearing waste using Thiobacillus ferrooxidans cells was studied. The effects on the rate of biooxidation were determined for two solid fractions. The logistic equation was used to descried experimental data.
EN
The application of biotechnological methods in the metallurgical industry has the potential to provide an environmentally friendly and cost-effective direction of development. Thiobacillus ferrooxidans, a thionic bacterium, and the microalga Chlamydomonas reinhardtii TN-72 CH were used as complex reagents for extracting gold from sulfide mineral raw materials. The sorption properties of modal and productive multicomponent gold-bearing solutions were studied. The sorption characteristics of the biosorbents were compared with those of sorbents currently used in gold production – the synthetic resin AM2B and GoldCarb activated carbon. The conducted research studying the sorption properties and survival ability of the microalga C. reinhardtii TN-72 CH will make it possible to develop an industrial technology for extracting metal in the hydrometallurgical cycle of gold production. The use of microorganisms in gold hydrometallurgy as an alternative to cyanide methods will reduce the load on the environment while reducing the cost of the technology. In the process of leaching gold-bearing raw materials by microorganisms, even submicroparticles of gold are released, which makes the processing of poor and refractory ores promising. Preliminary biooxidation increases the effectiveness of thiosulfates in terms of both time and gold recovery.
6
Content available Bacterial desulphurization of coal
71%
EN
The aim of this paper is to evaluate the suitability of a coal samples from different mines from Poland and Czech Republic for bacterial leaching. Laboratory research used a pure bacterial culture of Thiobacillus ferrooxidans. Were tested the samples from this localities: Mine Marcel, Mine Jankowice, Mine Staszic (Poland) and Mine Darkov and Mine Dukla (Czech Republic). The results showed that bacterial leaching was effective, with one month leaching time, when total desulphurization is from 38% to 72% and desulphurization of pyritic sulphur is from 60% to 82%. The paper describes changes of coal macerates after bacterial leaching.
PL
Celem tego artykułu jest ocena próbek węgla z różnych kopalń Polski i Czech pod kątem ługowania bakteryjnego. W badaniach laboratoryjnych zastosowano czystą kulturę bakterii Thiobacillus ferrooxidans. Testowano próbki z następujących kopalń: "Marcel", "Jankowice", "Staszic" (Polska) oraz "Darkov" i "Dukla" (Czechy). Wyniki badań wykazały, że ługowanie bakteryjne było efektywne w czasie jednego miesiąca, kiedy to ogólne odsiarczanie wzrosło z 38% do 72%, a odsiarczanie siarki pirytowej z 60% do 82%. Artykuł opisuje zmiany węgla po ługowaniu bakteryjnym.
EN
Kinetics of the process of microbiological oxidation of synthetic CuS performed with the involvement of pure and mixed cultures of T. ferrooxidans and T. lluooxidans bacteria were studied. The CuS oxidation with T. ferrooxidans bacteria was found to be best described by the model of inhibition of the first order with respect to the substrate and the product-inhibitor, while the process with T. thiooxidans and mixed cultures of these bacteria is best described by the first order reaction with respect to the substrate. It was also shown that the adaptation of the bacteria to the CuS tested significantly shortens the induction period and increases reaction rates. The optimum conditions of CuS oxidation were established. The yield of the reaction was established as ca. 30% and an increase in the reaction rate was observed when using mixed cultures of T. feirooxidans i T. thiooxidans bacteria adapted to CuS at 35ºC, in the medium containing 1 % (wt./vol.) CuS at the initial pH of the medium of 1.82.
EN
The use of Thiobacillus ferrooxidans bacteria in the process of copper and iron leaching from chalcopyrite coming from Kotlina Klodzka was investigated. The influence of the mineral content in the leaching solution the pH value and refinement of chalcopyrite on the subsequent stages of leaching was established. The process was described by the 1st order reaction inhibited by one of the products (Cu2+). Assuming this model, the kinetic parameters of leaching were determined.
EN
The kinetics of pyrite oxidation by Thiobacillus ferrooxidans bacteria were studied in different conditions of reaction (different size of pyrite sample relative to the leaching medium, medium pH and temperature). A model of the kinetics of the process has been proposed according to which it can be described by an autocatalytic reaction of order II, i.e. I order with respect to pyrite iron and I order with respect to the forming Fe(III) ions. On the basis of this model the rate constants and induction times of the reactions taking place in different conditions have been determined. The results obtained within the model enable us to show the optimum conditions of microbiological oxidation of pyrite.
EN
This paper reports results of studies on the influence of the crystallographic mineral structure on the process of pyrite and marcasite leaching. Kinetic studies show that the crystallographic structure of minerals like FeS2 type does not influence the efficiency of the process.
EN
The ferrous sulphate, which is a waste product in titanium white production at the Chemical Plant "Police" S.A., was subjected to microbiological oxidation with Thiobacillus ferrooxidans bacteria. The kinetic parameters of the culture growth were calculated on the basis of the Monod equation. The process was found to be best described by the model of the autocatalytic 1st order reaction with respect to the product and 1st order reaction with respect to the substrate. The effect of temperature and pH on the course of the process was studied. The kinetics of oxidation of ferrous ions coming from the waste ferrous sulphate was studied in the process with laboratory bacteria strain as well as the strain adapted to the waste product and compared with that of pure substrate oxidation. Analysis of the precipitates formed during microbiological oxidation of the waste ferrous sulphate proved that (NH4)Fe3(SO4)2(OH)6 with the admixture of NaFe3(SO4)2(OH)6 and KFe3(SO4)2(OH)6 are formed.
14
Content available remote Bacterial leaching of nickel and cobalt from pentlandite.
59%
EN
The influence of Thiobacillus ferrooxidans bacteria on efficiency of nickel and cobalt leaching from natural pentlandite (Ni,Fe)9S8 have been examined. The effect of pulp density, particle size and initial ferrous ion concentration in leaching solution. on the leaching yield was also evaluated. It has been demonstrated that the presence of T.ferrooxidans bacteria in leaching system induced considerable increase in nickel and cobalt leaching from pentlandite. The decrease in efficiencies of nickel and cobalt bacterial leaching processes have been denoted in systems containing. high amounts of ferrous ions. Initial Fe2+ concnentarion of 4.5 g/dm3 seems to be the most favorable for pentlandite bioleaching. The 20% pulp density may be admitted to be optimum regarding both satisfactory yields of bioleaching process and high nickel and cobalt concentrations in leaching solutions. The obtained results showed that particle size of 90-125 m was optimum for nickel and cobalt bioleaching from pentlandite.
PL
Badano wpływ bakterii Thiobacillus ferrooxidans na efektywność ługowania niklu i kobaltu z naturalnego pentlandutu (Ni, Fe)9S8, zawierającego 5,21% Ni 51.10% FE i 0.25% Co. Oceniano także wpływ gęstości pulpy (1%, 5%, 20%), rozmiaru ziaren (36-63 mm, 90-125 mm, 200-250mm, 63-200um) i początkowego stężenia jonu żelazawego Fe(II) w roztworze ługujacym (4,5 g/dm3, 9,0g/dm3, 13.5 g/dm3) na wydajność ługowania. Wykazano, że obecność bakterii T. Ferrooxidans w układzie ługujacym powodowała istotne zwiększenie wyługowania niklu i kobaltu z pentlandytu. W układach zawierających wysokie stężenie jonów żelazawych (?9 g/dm3)odnotowano zmniejszenie efektywności procesów bakteryjnego ługowania niklu i kobaltu. Wydaje się, że najbardziej korzystne dlabioługowania pentlandytu jest początkowe stężenie Fe(II) wynoszące 4.5 g/dm3. Biorąc pod uwagę zarówno satysfakcjonujące wydajności procesów bioługowania, jak i wysokie stężenia niklu i kobaltu w roztworach ługujacych, można przyjąć 20%-ową gęstość pulpy jako otymalną. Wielkość ziaren pentlandytu, optymalna dla bioługowania nuklu i kobaltu z tego minerału, powinna mieścić się w zakresie 90-125mm.
15
Content available remote Biooxidation of mining tailings from Zloty Stok.
59%
EN
The biooxidation of gold-bearing arsenic concentrate from mining tailing was investigated. The strain of Thiobacillus ferrooxidans isolated from the Zloty Stok tailing heaps was used. The chemical and biooxidation processes were monitored by checking the ferrous, ferric and arsenic concentration in the leaching solution. Leaching experiments, were conducted using both coarse (-0.5 +0.125 mm) and fine (-0.045 mm) fractions. The samples were examined. by means of the specific surface area measurements and the X-ray diffraction analysis. The small differences were observed during the oxidation of coarse and fine fractions. The slow chemical dissolution of loellingite (AsFe2) a main arsenic-bearing mineral, was supported by X-ray diffraction anal. In the case of a fine fraction oxidation, the precipitation of ferric arsenate was responsible for the lower Fe and As readings. The production of new phase was also supported by the FTIR spectra. Obtained results suggest that the direct biooxidation mechanism was responsible for the arsenic-bearing concentrate biooxidation.
PL
Przeprowadzone wcześniej badania wykazują, że odpady górnicze zgromadzone na Hałdzie Jan koło Złotego Stoku stanowią potencjalny surowiec do otrzymania złota. Przedstawiona Praca zawiera wyniki badań nad procesem bioutleniania próbek mineralnych pobranych z hałdy Jan. W badaniach użyto homogenizowanych bakterii Thiobacillus ferrooxidations wcześniej wyselekcjonowanych z tego złoża. Próbom bioługowania poddano grubo i drobnoziarnistą frakcję surowca. Przebieg procesu bioutleniania analizowane przez kontrole zmian stężenia jonów Fe(II), Fe(III), As przez pH roztworu. Określono zmiany w powierzchni właściwej próbek mineralnych wywołane procesem bioutleniania. Zachowanie gruboziarnistej próbki mineralnej mało różni się od chemicznego i biologicznego utleniania materiału drobnoziarnistego. Badania rentgenowskie wskazują na łatwiejsze bioutleniania loellingitu w porównaniu z procesem chemicznym. Zmniejszenie stężenia jonów arsenu w roztworze w końcowym okresie chemicznego ługowania należy tłumaczyć wytrąceniem się arseninu żelaza. W przypadku zastosowania pożywki 9K do bioługowania stężenia arsenu w roztworze spadło do zera. Badania spektroskopowe potwierdzają powstanie arseninu żelaza w procesie bioutleniania drobnoziarnistej frakcji odpadów górniczych z hałdy Jan.
EN
Metabolic activities of the museum and autochthonous strains of T. ferrooxidans bacteria, growing at temperatures 5, 10, 30 and 40°C in a liquid culture medium adjusted to pH 1.55, 1.8 or 2.3, were compared. The analysis of the dynamics of ferrous ion oxidation as well as bioextraction rate of titanium contained in wastes resulting from mining and burning lignite was carried out. The autochthonous bacteria proved to be less susceptible to temperature changes and medium acidity than the museum bacteria.
EN
The influence of fly ash from the "Karolin" heat and power producing plant in Poznan on the kinetics of processes taking place with involvement of the bacteria Desulfotomaculum ruminis and Thiobacillus ferrooxidans has been studied under laboratory conditions. The results indicate that the presence of fly ash has an inhibitory effect on the processes related to the microbiological conversion cycle of sulphur compounds and can be used as biocides in the processes of microbiological corrosion of materials.
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