TY  - JOUR
AU  - Tasić, Aleksandra M.
AU  - Sredović-Ignjatović, Ivana
AU  - Ignjatović, Ljubiša M.
AU  - Andjelković, Ivan B.
AU  - Antić, Mališa
AU  - Rajaković, Ljubinka V.
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4163
AB  - This paper presents the extraction of major and trace elements from a coal sample, in deionized water, by using three different extraction techniques. Rotary mixing and ultrasonic extraction were examined for different extraction times, while the microwave-assisted extraction was performed at different temperatures. Metal concentrations (Na, K, Ca, Mg, Al, Fe, Mn, Be, Cd, Co, Cr, Hg, As, Ni, Se, Sb and Pb) in solution were determined employing inductively coupled plasma atomic emission spectrometry; whereas the results obtained for Na, K, Ca and Mg were compared employing ion chromatography. Comparing the rotary-and ultrasonic-assisted extractions, it was shown that the former technique was more efficient for the determination of Fe, Na and Pb, whereas the latter one proved more efficient for the determination of Co and Cr ions. Microwave-assisted extraction was shown to be the most efficient method for all the tested elements in coal. In addition, sequential extraction of the elements was realized using microwave digestion. The results of the sequential extraction experiments indicated associations of investigated elements with a mineral phase and organic matrix. Sequential extraction provided information on possible leaching of As, Cd, Co, Cr, Ni, Pb, Fe and Mn under environmental conditions.
PB  - Srpsko hemijsko društvo, Beograd
T2  - JOURNAL OF THE SERBIAN CHEMICAL SOCIETY
T1  - Investigation of different extraction procedures for the determination of major and trace elements in coal by ICP-AES and ion chromatography
EP  - 417
IS  - 4
SP  - 403
VL  - 81
DO  - 10.2298/JSC150429078T
ER  - 

@article{
author = "Tasić, Aleksandra M. and Sredović-Ignjatović, Ivana and Ignjatović, Ljubiša M. and Andjelković, Ivan B. and Antić, Mališa and Rajaković, Ljubinka V.",
year = "2016",
abstract = "This paper presents the extraction of major and trace elements from a coal sample, in deionized water, by using three different extraction techniques. Rotary mixing and ultrasonic extraction were examined for different extraction times, while the microwave-assisted extraction was performed at different temperatures. Metal concentrations (Na, K, Ca, Mg, Al, Fe, Mn, Be, Cd, Co, Cr, Hg, As, Ni, Se, Sb and Pb) in solution were determined employing inductively coupled plasma atomic emission spectrometry; whereas the results obtained for Na, K, Ca and Mg were compared employing ion chromatography. Comparing the rotary-and ultrasonic-assisted extractions, it was shown that the former technique was more efficient for the determination of Fe, Na and Pb, whereas the latter one proved more efficient for the determination of Co and Cr ions. Microwave-assisted extraction was shown to be the most efficient method for all the tested elements in coal. In addition, sequential extraction of the elements was realized using microwave digestion. The results of the sequential extraction experiments indicated associations of investigated elements with a mineral phase and organic matrix. Sequential extraction provided information on possible leaching of As, Cd, Co, Cr, Ni, Pb, Fe and Mn under environmental conditions.",
publisher = "Srpsko hemijsko društvo, Beograd",
journal = "JOURNAL OF THE SERBIAN CHEMICAL SOCIETY",
title = "Investigation of different extraction procedures for the determination of major and trace elements in coal by ICP-AES and ion chromatography",
pages = "417-403",
number = "4",
volume = "81",
doi = "10.2298/JSC150429078T"
}

Tasić, A. M., Sredović-Ignjatović, I., Ignjatović, L. M., Andjelković, I. B., Antić, M.,& Rajaković, L. V.. (2016). Investigation of different extraction procedures for the determination of major and trace elements in coal by ICP-AES and ion chromatography. in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY
Srpsko hemijsko društvo, Beograd., 81(4), 403-417.
https://doi.org/10.2298/JSC150429078T

Tasić AM, Sredović-Ignjatović I, Ignjatović LM, Andjelković IB, Antić M, Rajaković LV. Investigation of different extraction procedures for the determination of major and trace elements in coal by ICP-AES and ion chromatography. in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY. 2016;81(4):403-417.
doi:10.2298/JSC150429078T .

Tasić, Aleksandra M., Sredović-Ignjatović, Ivana, Ignjatović, Ljubiša M., Andjelković, Ivan B., Antić, Mališa, Rajaković, Ljubinka V., "Investigation of different extraction procedures for the determination of major and trace elements in coal by ICP-AES and ion chromatography" in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY, 81, no. 4 (2016):403-417,
https://doi.org/10.2298/JSC150429078T . .

TY  - JOUR
AU  - Sredović-Ignjatović, Ivana
AU  - Onjia, Antonije E.
AU  - Ignjatović, Ljubiša M.
AU  - Todorović, Zaklina N.
AU  - Rajaković, Ljubinka V.
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3706
AB  - Determination of total halogens in coal was investigated with oxygen bomb combustion followed by ion chromatography. Experimental parameters were optimized by fractional factorial design and response surface methodology. Fractional factorial design was employed in screening experiments to evaluate the influence of the oxygen pressure, catalyst, absorption solution, reduction reagent, bomb cooling time, and a combustion aid on the combustion of coal in an oxygen bomb. Response surface methodology was conducted to further refine the results obtained by fractional factorial design and to define parameters for the procedure. The accuracy and precision of combustion with ion chromatography were evaluated by the use of two certified reference materials and by fortified in-house coal standards. The limits of detection and quantification for total halogens were 0.84 and 2.80 milligrams per kilogram, respectively, for 500 milligram samples. Ion chromatography provided relative standard deviations less than 4 percent, recoveries exceeding 95 percent, and was convenient. This method is recommended for routine determination of total halogens in coal because of its reliability.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Analytical Letters
T1  - Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography
EP  - 2612
IS  - 16
SP  - 2597
VL  - 48
DO  - 10.1080/00032719.2015.1041029
ER  - 

@article{
author = "Sredović-Ignjatović, Ivana and Onjia, Antonije E. and Ignjatović, Ljubiša M. and Todorović, Zaklina N. and Rajaković, Ljubinka V.",
year = "2015",
abstract = "Determination of total halogens in coal was investigated with oxygen bomb combustion followed by ion chromatography. Experimental parameters were optimized by fractional factorial design and response surface methodology. Fractional factorial design was employed in screening experiments to evaluate the influence of the oxygen pressure, catalyst, absorption solution, reduction reagent, bomb cooling time, and a combustion aid on the combustion of coal in an oxygen bomb. Response surface methodology was conducted to further refine the results obtained by fractional factorial design and to define parameters for the procedure. The accuracy and precision of combustion with ion chromatography were evaluated by the use of two certified reference materials and by fortified in-house coal standards. The limits of detection and quantification for total halogens were 0.84 and 2.80 milligrams per kilogram, respectively, for 500 milligram samples. Ion chromatography provided relative standard deviations less than 4 percent, recoveries exceeding 95 percent, and was convenient. This method is recommended for routine determination of total halogens in coal because of its reliability.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Analytical Letters",
title = "Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography",
pages = "2612-2597",
number = "16",
volume = "48",
doi = "10.1080/00032719.2015.1041029"
}

Sredović-Ignjatović, I., Onjia, A. E., Ignjatović, L. M., Todorović, Z. N.,& Rajaković, L. V.. (2015). Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography. in Analytical Letters
Taylor & Francis Inc, Philadelphia., 48(16), 2597-2612.
https://doi.org/10.1080/00032719.2015.1041029

Sredović-Ignjatović I, Onjia AE, Ignjatović LM, Todorović ZN, Rajaković LV. Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography. in Analytical Letters. 2015;48(16):2597-2612.
doi:10.1080/00032719.2015.1041029 .

Sredović-Ignjatović, Ivana, Onjia, Antonije E., Ignjatović, Ljubiša M., Todorović, Zaklina N., Rajaković, Ljubinka V., "Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography" in Analytical Letters, 48, no. 16 (2015):2597-2612,
https://doi.org/10.1080/00032719.2015.1041029 . .

TY  - JOUR
AU  - Sredović-Ignjatović, Ivana
AU  - Onjia, Antonije E.
AU  - Ignjatović, Ljubiša M.
AU  - Todorović, Zaklina N.
AU  - Rajaković, Ljubinka V.
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5764
AB  - Determination of total halogens in coal was investigated with oxygen bomb combustion followed by ion chromatography. Experimental parameters were optimized by fractional factorial design and response surface methodology. Fractional factorial design was employed in screening experiments to evaluate the influence of the oxygen pressure, catalyst, absorption solution, reduction reagent, bomb cooling time, and a combustion aid on the combustion of coal in an oxygen bomb. Response surface methodology was conducted to further refine the results obtained by fractional factorial design and to define parameters for the procedure. The accuracy and precision of combustion with ion chromatography were evaluated by the use of two certified reference materials and by fortified in-house coal standards. The limits of detection and quantification for total halogens were 0.84 and 2.80 milligrams per kilogram, respectively, for 500 milligram samples. Ion chromatography provided relative standard deviations less than 4 percent, recoveries exceeding 95 percent, and was convenient. This method is recommended for routine determination of total halogens in coal because of its reliability.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Analytical Letters
T1  - Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography
EP  - 2612
IS  - 16
SP  - 2597
VL  - 48
DO  - 10.1080/00032719.2015.1041029
ER  - 

@article{
author = "Sredović-Ignjatović, Ivana and Onjia, Antonije E. and Ignjatović, Ljubiša M. and Todorović, Zaklina N. and Rajaković, Ljubinka V.",
year = "2015",
abstract = "Determination of total halogens in coal was investigated with oxygen bomb combustion followed by ion chromatography. Experimental parameters were optimized by fractional factorial design and response surface methodology. Fractional factorial design was employed in screening experiments to evaluate the influence of the oxygen pressure, catalyst, absorption solution, reduction reagent, bomb cooling time, and a combustion aid on the combustion of coal in an oxygen bomb. Response surface methodology was conducted to further refine the results obtained by fractional factorial design and to define parameters for the procedure. The accuracy and precision of combustion with ion chromatography were evaluated by the use of two certified reference materials and by fortified in-house coal standards. The limits of detection and quantification for total halogens were 0.84 and 2.80 milligrams per kilogram, respectively, for 500 milligram samples. Ion chromatography provided relative standard deviations less than 4 percent, recoveries exceeding 95 percent, and was convenient. This method is recommended for routine determination of total halogens in coal because of its reliability.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Analytical Letters",
title = "Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography",
pages = "2612-2597",
number = "16",
volume = "48",
doi = "10.1080/00032719.2015.1041029"
}

Sredović-Ignjatović, I., Onjia, A. E., Ignjatović, L. M., Todorović, Z. N.,& Rajaković, L. V.. (2015). Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography. in Analytical Letters
Taylor & Francis Inc, Philadelphia., 48(16), 2597-2612.
https://doi.org/10.1080/00032719.2015.1041029

Sredović-Ignjatović I, Onjia AE, Ignjatović LM, Todorović ZN, Rajaković LV. Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography. in Analytical Letters. 2015;48(16):2597-2612.
doi:10.1080/00032719.2015.1041029 .

Sredović-Ignjatović, Ivana, Onjia, Antonije E., Ignjatović, Ljubiša M., Todorović, Zaklina N., Rajaković, Ljubinka V., "Experimental Design Optimization of the Determination of Total Halogens in Coal by Combustion-Ion Chromatography" in Analytical Letters, 48, no. 16 (2015):2597-2612,
https://doi.org/10.1080/00032719.2015.1041029 . .

TY  - JOUR
AU  - Sredović-Ignjatović, Ivana
AU  - Rajaković, Ljubinka V.
PY  - 2010
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/2398
AB  - Corrosion effects in thermal power plants and environmental impact cause an increase in demand for fluorine analysis in coal. Solid sample decomposition, organic and inorganic fluorine compounds, volatility of fluorine species are problems which deserve a special attention. The aim of this work was to optimize the pyrohydrolytic (Phy) determination of fluorine content in the lignite coal. The parameters of pyrohydrolysis were evaluated and optimized by two statistical methods: Plackett-Burman (PB) design and response surface methodology (RSM). The content of fluorine in the absorption solution was measured by fluoride ion-selective electrode. The limit of detection of the proposed method was 20 mu g g(-1), with good recovery (95%) and relative standard deviation less than 5%. With such benefits as simplicity, precision, accuracy and economy, this method is highly suitable for routine analysis of coal.
PB  - Elsevier Science Bv, Amsterdam
T2  - Journal of Hazardous Materials
T1  - Pyrohydrolytic determination of fluorine in coal: A chemometric approach
EP  - 451
IS  - 1-3
SP  - 445
VL  - 177
DO  - 10.1016/j.jhazmat.2009.12.053
ER  - 

@article{
author = "Sredović-Ignjatović, Ivana and Rajaković, Ljubinka V.",
year = "2010",
abstract = "Corrosion effects in thermal power plants and environmental impact cause an increase in demand for fluorine analysis in coal. Solid sample decomposition, organic and inorganic fluorine compounds, volatility of fluorine species are problems which deserve a special attention. The aim of this work was to optimize the pyrohydrolytic (Phy) determination of fluorine content in the lignite coal. The parameters of pyrohydrolysis were evaluated and optimized by two statistical methods: Plackett-Burman (PB) design and response surface methodology (RSM). The content of fluorine in the absorption solution was measured by fluoride ion-selective electrode. The limit of detection of the proposed method was 20 mu g g(-1), with good recovery (95%) and relative standard deviation less than 5%. With such benefits as simplicity, precision, accuracy and economy, this method is highly suitable for routine analysis of coal.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Journal of Hazardous Materials",
title = "Pyrohydrolytic determination of fluorine in coal: A chemometric approach",
pages = "451-445",
number = "1-3",
volume = "177",
doi = "10.1016/j.jhazmat.2009.12.053"
}

Sredović-Ignjatović, I.,& Rajaković, L. V.. (2010). Pyrohydrolytic determination of fluorine in coal: A chemometric approach. in Journal of Hazardous Materials
Elsevier Science Bv, Amsterdam., 177(1-3), 445-451.
https://doi.org/10.1016/j.jhazmat.2009.12.053

Sredović-Ignjatović I, Rajaković LV. Pyrohydrolytic determination of fluorine in coal: A chemometric approach. in Journal of Hazardous Materials. 2010;177(1-3):445-451.
doi:10.1016/j.jhazmat.2009.12.053 .

Sredović-Ignjatović, Ivana, Rajaković, Ljubinka V., "Pyrohydrolytic determination of fluorine in coal: A chemometric approach" in Journal of Hazardous Materials, 177, no. 1-3 (2010):445-451,
https://doi.org/10.1016/j.jhazmat.2009.12.053 . .