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SM ISO690:2012 ZINICOVSCAIA, Inga, DUKA, Gh., RUDIK, V., CEPOI, Liliana, CHIRIAC, Tatiana, RUDI, Ludmila, FRONTASYEVA, Marina, PAVLOV, Sergey, GUNDORINA, Svetlana. Spirulina platensis as biosorbent of zinc in water. In: The International Conference dedicated to the 55th anniversary from the foundation of the Institute of Chemistry of the Academy of Sciences of Moldova, 28-30 mai 2014, Chișinău. Chișinău, Republica Moldova: Institutul de Chimie al AȘM, 2014, pp. 191-192. |
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The International Conference dedicated to the 55th anniversary from the foundation of the Institute of Chemistry of the Academy of Sciences of Moldova 2014 | |||||||
Conferința "The International Conference dedicated to the 55th anniversary from the foundation of the Institute of Chemistry of the Academy of Sciences of Moldova" Chișinău, Moldova, 28-30 mai 2014 | |||||||
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Heavy metals are known as a hazardous group of pollutants. The contamination by heavy contact. From the solution of zinc sulfate (0.34 mM) the spirulina biomass accumulated about |
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<?xml version='1.0' encoding='utf-8'?> <oai_dc:dc xmlns:dc='http://purl.org/dc/elements/1.1/' xmlns:oai_dc='http://www.openarchives.org/OAI/2.0/oai_dc/' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:schemaLocation='http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd'> <dc:creator>Zinicovscaia, I.</dc:creator> <dc:creator>Duca, G.G.</dc:creator> <dc:creator>Rudic, V.F.</dc:creator> <dc:creator>Cepoi, L.E.</dc:creator> <dc:creator>Chiriac, T.V.</dc:creator> <dc:creator>Rudi, L.B.</dc:creator> <dc:creator>Frontaseva, M.V.</dc:creator> <dc:creator>Pavlov, S.S.</dc:creator> <dc:creator>Gundorina, S.F.</dc:creator> <dc:date>2014</dc:date> <dc:description xml:lang='en'><p>Heavy metals are known as a hazardous group of pollutants. The contamination by heavy<br />metals causes a serious problem because they cannot be naturally degraded like organic<br />pollutants and they are accumulated in different parts of the food chain. Physical and chemical<br />methods have been proposed for the removal of these pollutants. Nevertheless, they have some<br />disadvantages, among them cost-effectiveness limitations, generation of hazardous by-products<br />or inefficiency when concentration of polluted materials is below 100 mg/l. Biological methods<br />help to avoid these drawbacks since they are easy to operate, do not produce secondary pollution<br />and show higher efficiency at low metalconcentrations. Microorganisms and plants are usually<br />used for the removal of heavy metals [1,5,7]. Mechanisms by which microorganisms act on<br />heavy metals include biosorption, bioleaching, biomineralization, intracellular accumulation<br />andenzyme-catalyzed transformations.<br />Microalgae have been found to be efficient biosorbents of metal ions from wastewater,<br />owing to their low cost, prompt availability, relatively high specific surface area and good<br />binding affinity [3,4].<br />Being used in electroplating (anti-corrosion agent), alloys, pigments in paints, organic<br />synthesis, agriculture, zinc falls within the aquatic environment, creating and advanced level of<br />pollution [2, 6].<br />To determine the biosorption of Zn cations by Spirulina platensis 0.75 g of biomass were<br />suspended in 100 mL of ZnSO4·7H2O solution (concentration 0.34 mM and 3.4 mM) in 250-mL<br />glass flasks on a rotary shaker set at 100 rpm. The process of zinc adsorption was studied during<br />1 hour. Samples were collected in 5, 15, 30 and 60 minutes.<br />For samples elemental content determination neutron activation analysis (NAA) at the pulsed<br />fast reactor IBR-2 (FLNP JINR, Dubna) was used. Samples with concentration of ZnSO4·7H2O<br />0.34 mM were irradiated for 2 days and their activity measured in 4 days. The zinc content was<br />determined by γ-line with the energy 1115.5 keV of isotope 65Zn.<br />For samples with concentration of ZnSO4·7H2O 3.4 mM the irradiation time was 30 min<br />and Zn concentration was determined by γ-line with the energy 438.6 keV of isotope 69mZn.<br />The NAA data processing and determination of element concentrations were performed<br />using software developed in FLNP JINR.<br />The conventional techniques to remove toxic metals such as ion exchange and<br />precipitation are considered to be inefficient and too expensive when the zinc ion concentration<br />in the aquatic environment is lower than 100 mg/l. In our case in the first experiment the<br />concentration of zinc was 22.6 mg/l. In the second experiment the concentration of zinc in<br />solution was higher. In this case the microbial metal removal and traditional technologies of<br />water purification can be efficiently applied.<br />In the case of zinc sulfate with a concentration of 0.34 mM the zinc content in biomass<br />during the first 5 min of interaction grows up from 50 to 900 μg/g and further accumulation is<br />observed, no saturation occurs. The rate of biosorption of zinc from solutions after the first five<br />minutes of contact decreases gradually, but stable growth is recorded within 60 minutes of</p><p>contact. From the solution of zinc sulfate (0.34 mM) the spirulina biomass accumulated about<br />56% of zinc ions (1700 μg/g). At the ZnSO4 concentration of 3.4 mM (Fig.1b) the rate of metal<br />removal from solution was very rapid in the first 5 min (from 50 to 9000 μg/g) then it did not<br />change significantly. In this case the spirulina biomass accumulated 6.75mg of zinc ions from<br />22.6mg present in 100 ml of solution. The extension of the contact time of interaction of 3.4mM<br />zinc sulfate solution with the spirulina biomass does not lead to the additional accumulation of<br />the metal ions. Thus, in the case of a high concentration of zinc ions in the solution the efficiency<br />of the spirulina biomass as a sorbent is lower.<br />The potential application of microorganisms for water treatment is an efficient method. Spirulina<br />biomass can be successfully used for zinc removal from wastewater at low zinc concentration,<br />when conventional techniques are unprofitable. Spirulina cyanobacteria can be efficiently used<br />for the processes of water post-treatment and as a matrix for zinc-containing drugs<br />The work was funancially supported by JINR GRANT № 13-402-03 and institutional project<br />11.817.08.18F<br />References:<br />[1] Farooq, U.; Kozinski, J. A.; Ain Khan, M.; Athar, M. Biosorption of heavy metal ions using<br />wheat based biosorbents – A review of the recent literature. In: Bioresour. Technol. 2010,<br />101, 5043–5053.<br />[2] King, P.; Anuradha, K.; Beena Lahari, S.; Prasanna Kumar, Y.; Prasad, V. S. R. K.<br />Biosorption of zinc from aqueous solution using Azadirachta indica bark: Equilibrium and<br />kinetic studies. In: J. Hazard. Mater. 2008, 152, 324–329.<br />[3] Monteiro, C. M.; Castro, P. M. L.; Malcata, F. X. Biosorption of zinc ions from aqueous<br />solution by the microalga Scenedesmus obliquus. In: Environ. Chem. Lett. 2011, 9(2), 169-<br />176.<br />[4] Morsy, F. M.; Hassan, S. H. A.; Koutb, M. Biosorption of Cd(II) and Zn(II) by Nostoc<br />commune: Isotherm and Kinetics Studies. In: CLEAN – Soil, Air, Water. 2011, 39 (7), 680-<br />687.<br />[5] Vecchi,o A.; Finoli, C.; Di Simine, D.; Andreoni, V. Heavy metal biosorption by bacterial<br />cells. In: Fresenius J. Anal. Chem. 1998, 361, 338–342.<br />[6] Venkateswarlu, P.; Vijaya Durga, G.; Chitti Babu, N.; Venkateswara Rao, M. Biosorption of<br />Zn(II) from an aqueous solution by Erythrina variegata orientalis leaf powder. In: Int. J.<br />Phys. Sci. 2008, 3 (9), 197-204.<br />[7] Vijayaraghavan, K.; Yun, Y. S. Bacterial biosorbents and biosorption. In: Biotechnol. Adv.<br />2008, 26, 266–291.</p></dc:description> <dc:source>The International Conference dedicated to the 55th anniversary from the foundation of the Institute of Chemistry of the Academy of Sciences of Moldova () 191-192</dc:source> <dc:title>Spirulina platensis as biosorbent of zinc in water</dc:title> <dc:type>info:eu-repo/semantics/article</dc:type> </oai_dc:dc>