TY  - CONF
AU  - Joksimović, K.
AU  - Žerađanin, A.
AU  - Lončarević, B.
AU  - Lješević, Marija
AU  - Avdalović, J.
AU  - Ranđelović, Danijela
AU  - Beškoski, Vladimir
PY  - 2021
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/4916
AB  - Introduction: Global worldwide population and urbanization in general have created an increasing need for new energy sources. These sources need to be renewable, but it is also very important to respect the principles of environmental protection. Microbial fuel cells (MFC) are a green technology that is attracting more and more attention in the last decade. MFC presents a system which produces electrical current through metabolic processes of microorganisms such is the decomposition of organic matter. In this process chemical energy is directly converted into electrical energy [1-3]. The performance of MFC depends on several factors: temperature, the composition of the sediment, the material from which the electrodes are made, but certainly, one of the prominent factors is the activity of a microbial community. In this paper, efficiency of two MFC systems will be compared to obtain the highest current and power generation. One of them contains only river sediment as a source of microorganisms, while the other was biostimulated by microorganisms isolated from the same river sediment [2-3]. Methods: The river sediment was placed between a set of inox electrodes in a plastic container, with a total volume of 201 cm3  (MFC I). The second MFC (MFC II) was made in the same way, but a consortium of microorganisms, Clostridium sp., Bacillus sp. and Tepidibacter sp. isolated from the river sediment was added to the sediment. The set of resistors already established in our previous studies were used for the measurement of the amount of voltage, which was then used to obtained the values of current and power [4]. Results: After five days of measuring the generated voltage via MFC I and II, the results for current and power density were obtained. In MFC I, the highest current density was recorded on the fifth day and was 76 mA/ m3  while the power was 1.5 mW/m3 . With MFC II, the results were visibly higher, where the current was increased three times (up to 210 mA/m3 ), and the power by as much as 4 times higher compared to the results of MFC I (6 mW/m3 ). Conclusion: Results show that MFC I has lower values than the sediment stimulated by a consortium of microorganisms in the MFC II. The community of microorganisms greatly contributes to improving the performance of the sediment itself, by generating more power density.
PB  - Belgrade : Serbian Chemical Society
C3  - Book of Abstracts 21st; European Meeting on Environmental Chemistry
T1  - Influence of Microbial Community on Power Generation Using MFC System
SP  - 112
EP  - 112
UR  - https://hdl.handle.net/21.15107/rcub_cherry_4916
ER  - 

@conference{
author = "Joksimović, K. and Žerađanin, A. and Lončarević, B. and Lješević, Marija and Avdalović, J. and Ranđelović, Danijela and Beškoski, Vladimir",
year = "2021",
abstract = "Introduction: Global worldwide population and urbanization in general have created an increasing need for new energy sources. These sources need to be renewable, but it is also very important to respect the principles of environmental protection. Microbial fuel cells (MFC) are a green technology that is attracting more and more attention in the last decade. MFC presents a system which produces electrical current through metabolic processes of microorganisms such is the decomposition of organic matter. In this process chemical energy is directly converted into electrical energy [1-3]. The performance of MFC depends on several factors: temperature, the composition of the sediment, the material from which the electrodes are made, but certainly, one of the prominent factors is the activity of a microbial community. In this paper, efficiency of two MFC systems will be compared to obtain the highest current and power generation. One of them contains only river sediment as a source of microorganisms, while the other was biostimulated by microorganisms isolated from the same river sediment [2-3]. Methods: The river sediment was placed between a set of inox electrodes in a plastic container, with a total volume of 201 cm3  (MFC I). The second MFC (MFC II) was made in the same way, but a consortium of microorganisms, Clostridium sp., Bacillus sp. and Tepidibacter sp. isolated from the river sediment was added to the sediment. The set of resistors already established in our previous studies were used for the measurement of the amount of voltage, which was then used to obtained the values of current and power [4]. Results: After five days of measuring the generated voltage via MFC I and II, the results for current and power density were obtained. In MFC I, the highest current density was recorded on the fifth day and was 76 mA/ m3  while the power was 1.5 mW/m3 . With MFC II, the results were visibly higher, where the current was increased three times (up to 210 mA/m3 ), and the power by as much as 4 times higher compared to the results of MFC I (6 mW/m3 ). Conclusion: Results show that MFC I has lower values than the sediment stimulated by a consortium of microorganisms in the MFC II. The community of microorganisms greatly contributes to improving the performance of the sediment itself, by generating more power density.",
publisher = "Belgrade : Serbian Chemical Society",
journal = "Book of Abstracts 21st; European Meeting on Environmental Chemistry",
title = "Influence of Microbial Community on Power Generation Using MFC System",
pages = "112-112",
url = "https://hdl.handle.net/21.15107/rcub_cherry_4916"
}

Joksimović, K., Žerađanin, A., Lončarević, B., Lješević, M., Avdalović, J., Ranđelović, D.,& Beškoski, V.. (2021). Influence of Microbial Community on Power Generation Using MFC System. in Book of Abstracts 21st; European Meeting on Environmental Chemistry
Belgrade : Serbian Chemical Society., 112-112.
https://hdl.handle.net/21.15107/rcub_cherry_4916

Joksimović K, Žerađanin A, Lončarević B, Lješević M, Avdalović J, Ranđelović D, Beškoski V. Influence of Microbial Community on Power Generation Using MFC System. in Book of Abstracts 21st; European Meeting on Environmental Chemistry. 2021;:112-112.
https://hdl.handle.net/21.15107/rcub_cherry_4916 .

Joksimović, K., Žerađanin, A., Lončarević, B., Lješević, Marija, Avdalović, J., Ranđelović, Danijela, Beškoski, Vladimir, "Influence of Microbial Community on Power Generation Using MFC System" in Book of Abstracts 21st; European Meeting on Environmental Chemistry (2021):112-112,
https://hdl.handle.net/21.15107/rcub_cherry_4916 .

TY  - CONF
AU  - Joksimović, K.
AU  - Avdalović, J.
AU  - Zildžović, S.
AU  - Dojčinović, B.
AU  - Milić, Jelena
AU  - Lugonja, N.
AU  - Beškoski, Vladimir
PY  - 2021
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/4931
AB  - Recycling of electronic waste is crucial not only from the viewpoint of waste treatment but also from aspect of the recovery of valuable metals [1]. The aim of our study was to investigate the potential of using the Acidithiobacillus sp. B2, to solubilize metals (Cu and Zn) from electronic waste. Methodology: Chemical analysis of electronic waste and pyrite The electronic waste (after separating of the plastic parts) and pyrite were pulverized and sieved through a 63 µm stainless steel sieve in preparation for chemical and leaching studies. Electronic waste preparation for the leaching experiment The presence of alkali components in electronic waste is considered inconvenient for the reaction between the electronic waste and the acidic iron(III) sulphate solution. Hence, it is necessary to neutralize the electronic waste before adding the bacterial culture which would generate the oxidant. Before the leaching experiment, electronic waste was dispersed in 0.05 M H2 SO4  solution, shaken for 48 h, filtered from the solution, washed out with deionized water and dried at 110 °C [2]. Preparation of pyrite for the leaching experiments The pyrite concentrate for the leaching experiments was prepared by treating with a 0.5 mol/dm3  sulphuric acid solution (pH ~ 0.5) (solid to liquid phase ratio 1:5 m/V), and mixing with a mechanical stirrer at a room temperature overnight. Then, the solution was decanted, washed with deionized water and dried at 80 °C to a constant mass [2]. Leaching experiments The leaching experiments were carried out with bacterium Acidithiobacillus sp. B2. Experimental conditions were: leaching period of 20 d, 50 ml leaching solution (g/dm3 ): (NH4 )2 SO4  (3), K2 HPO4  (0.5), MgSO4 x 7H2 O(0.5), KCl (0.1), Ca(NO3 )2  (0.01), at a pH of 2.5 in 150 mL Erlenmeyer flasks at a pulp density of 10% (m/V) (5 g leaching substrate in 50 ml solution). The pH of the leaching solution was maintained at a constant value during the leaching process. One half of the substrate was pyrite and the other was an electronic waste. The initial number of microogranisms was 107  per mL, determined by the Most Probable Number method. The control suspension had the same chemical content and pH value as the suspension with Acidithiobacillus sp. B2 but the Acidithiobacillus sp. B2 culture had been inactivated by sterilization. The study was realized on a horizontal shaker. The incubation temperature was 28 °C [2]. Results and conclusions: The results of the effective metal leaching (calculated by subtraction of percentage metal leaching in the control suspension from that in the Acidithiobacillus sp. B2 suspension) are as follows: Zn (38%)>Cu (35%). The obtained results demonstrate that Acidithiobacillus sp. B2 was able to grow in the presence of electronic waste and may be “green” agents in the area of circular economy and sustainable development.
PB  - Belgrade : Serbian Chemical Society
C3  - Book of Abstracts 21st; European Meeting on Environmental Chemistry
T1  - Microbial Recovery of Copper and Zinc from Wasted Electronic Parts
SP  - 165
EP  - 165
UR  - https://hdl.handle.net/21.15107/rcub_cherry_4931
ER  - 

@conference{
author = "Joksimović, K. and Avdalović, J. and Zildžović, S. and Dojčinović, B. and Milić, Jelena and Lugonja, N. and Beškoski, Vladimir",
year = "2021",
abstract = "Recycling of electronic waste is crucial not only from the viewpoint of waste treatment but also from aspect of the recovery of valuable metals [1]. The aim of our study was to investigate the potential of using the Acidithiobacillus sp. B2, to solubilize metals (Cu and Zn) from electronic waste. Methodology: Chemical analysis of electronic waste and pyrite The electronic waste (after separating of the plastic parts) and pyrite were pulverized and sieved through a 63 µm stainless steel sieve in preparation for chemical and leaching studies. Electronic waste preparation for the leaching experiment The presence of alkali components in electronic waste is considered inconvenient for the reaction between the electronic waste and the acidic iron(III) sulphate solution. Hence, it is necessary to neutralize the electronic waste before adding the bacterial culture which would generate the oxidant. Before the leaching experiment, electronic waste was dispersed in 0.05 M H2 SO4  solution, shaken for 48 h, filtered from the solution, washed out with deionized water and dried at 110 °C [2]. Preparation of pyrite for the leaching experiments The pyrite concentrate for the leaching experiments was prepared by treating with a 0.5 mol/dm3  sulphuric acid solution (pH ~ 0.5) (solid to liquid phase ratio 1:5 m/V), and mixing with a mechanical stirrer at a room temperature overnight. Then, the solution was decanted, washed with deionized water and dried at 80 °C to a constant mass [2]. Leaching experiments The leaching experiments were carried out with bacterium Acidithiobacillus sp. B2. Experimental conditions were: leaching period of 20 d, 50 ml leaching solution (g/dm3 ): (NH4 )2 SO4  (3), K2 HPO4  (0.5), MgSO4 x 7H2 O(0.5), KCl (0.1), Ca(NO3 )2  (0.01), at a pH of 2.5 in 150 mL Erlenmeyer flasks at a pulp density of 10% (m/V) (5 g leaching substrate in 50 ml solution). The pH of the leaching solution was maintained at a constant value during the leaching process. One half of the substrate was pyrite and the other was an electronic waste. The initial number of microogranisms was 107  per mL, determined by the Most Probable Number method. The control suspension had the same chemical content and pH value as the suspension with Acidithiobacillus sp. B2 but the Acidithiobacillus sp. B2 culture had been inactivated by sterilization. The study was realized on a horizontal shaker. The incubation temperature was 28 °C [2]. Results and conclusions: The results of the effective metal leaching (calculated by subtraction of percentage metal leaching in the control suspension from that in the Acidithiobacillus sp. B2 suspension) are as follows: Zn (38%)>Cu (35%). The obtained results demonstrate that Acidithiobacillus sp. B2 was able to grow in the presence of electronic waste and may be “green” agents in the area of circular economy and sustainable development.",
publisher = "Belgrade : Serbian Chemical Society",
journal = "Book of Abstracts 21st; European Meeting on Environmental Chemistry",
title = "Microbial Recovery of Copper and Zinc from Wasted Electronic Parts",
pages = "165-165",
url = "https://hdl.handle.net/21.15107/rcub_cherry_4931"
}

Joksimović, K., Avdalović, J., Zildžović, S., Dojčinović, B., Milić, J., Lugonja, N.,& Beškoski, V.. (2021). Microbial Recovery of Copper and Zinc from Wasted Electronic Parts. in Book of Abstracts 21st; European Meeting on Environmental Chemistry
Belgrade : Serbian Chemical Society., 165-165.
https://hdl.handle.net/21.15107/rcub_cherry_4931

Joksimović K, Avdalović J, Zildžović S, Dojčinović B, Milić J, Lugonja N, Beškoski V. Microbial Recovery of Copper and Zinc from Wasted Electronic Parts. in Book of Abstracts 21st; European Meeting on Environmental Chemistry. 2021;:165-165.
https://hdl.handle.net/21.15107/rcub_cherry_4931 .

Joksimović, K., Avdalović, J., Zildžović, S., Dojčinović, B., Milić, Jelena, Lugonja, N., Beškoski, Vladimir, "Microbial Recovery of Copper and Zinc from Wasted Electronic Parts" in Book of Abstracts 21st; European Meeting on Environmental Chemistry (2021):165-165,
https://hdl.handle.net/21.15107/rcub_cherry_4931 .