TY  - JOUR
AU  - Nikolić, Marija S.
AU  - Petrović, Rada
AU  - Veljović, Đorđe N.
AU  - Ćosović, Vladan
AU  - Stanković, Nadežda
AU  - Đonlagić, Jasna A.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1899
AB  - Poly(epsilon-caprolactone) (PCL) based nanocomposites with unmodified and organomodified sepiolites were prepared by solution casting method. The sepiolites were modified with short (3-mercaptopropyl)trimethoxysilane (SEP-SI) by using covalent grafting or with long hexadecylamine (SEP-HDA) by using ionic exchange. In order to reveal the influence of the organomodification on the nanoclay dispersion and the properties of the nano composites XRD, DSC, TG, SEM, TEM, optical microscopy, melt rheology and dynamic-mechanical analyses were performed. A better dispersion was achieved when organomodified sepiolites instead of native ones were used as fillers. As deduced from the melt rheology data, by analysis of the Cole-Cole plots, the best dispersion was obtained for SEP-SI nanoclay. The thermal stability was not improved, however in the initial stages of the thereto-oxidative degradation a delay in the weight loss was observed for nanocomposites with organomodified sepiolites. The mechanical properties of the nanocomposites were improved in comparison to PCL, particularly for those with modified sepiolites. In terms of mechanical properties the use of sepiolite modified with HDA gave the best results, as a consequence of better interaction between longer alkyl hydrophobic part of the organic modificator and the hydrophobic PCL matrix.
T2  - European Polymer Journal
T1  - Effect of sepiolite organomodification on the performance of PCL/sepiolite nanocomposites
VL  - 97
SP  - 198
EP  - 209
DO  - 10.1016/j.eurpolymj.2017.10.010
ER  - 

@article{
author = "Nikolić, Marija S. and Petrović, Rada and Veljović, Đorđe N. and Ćosović, Vladan and Stanković, Nadežda and Đonlagić, Jasna A.",
year = "2017",
abstract = "Poly(epsilon-caprolactone) (PCL) based nanocomposites with unmodified and organomodified sepiolites were prepared by solution casting method. The sepiolites were modified with short (3-mercaptopropyl)trimethoxysilane (SEP-SI) by using covalent grafting or with long hexadecylamine (SEP-HDA) by using ionic exchange. In order to reveal the influence of the organomodification on the nanoclay dispersion and the properties of the nano composites XRD, DSC, TG, SEM, TEM, optical microscopy, melt rheology and dynamic-mechanical analyses were performed. A better dispersion was achieved when organomodified sepiolites instead of native ones were used as fillers. As deduced from the melt rheology data, by analysis of the Cole-Cole plots, the best dispersion was obtained for SEP-SI nanoclay. The thermal stability was not improved, however in the initial stages of the thereto-oxidative degradation a delay in the weight loss was observed for nanocomposites with organomodified sepiolites. The mechanical properties of the nanocomposites were improved in comparison to PCL, particularly for those with modified sepiolites. In terms of mechanical properties the use of sepiolite modified with HDA gave the best results, as a consequence of better interaction between longer alkyl hydrophobic part of the organic modificator and the hydrophobic PCL matrix.",
journal = "European Polymer Journal",
title = "Effect of sepiolite organomodification on the performance of PCL/sepiolite nanocomposites",
volume = "97",
pages = "198-209",
doi = "10.1016/j.eurpolymj.2017.10.010"
}

Nikolić, M. S., Petrović, R., Veljović, Đ. N., Ćosović, V., Stanković, N.,& Đonlagić, J. A.. (2017). Effect of sepiolite organomodification on the performance of PCL/sepiolite nanocomposites. in European Polymer Journal, 97, 198-209.
https://doi.org/10.1016/j.eurpolymj.2017.10.010

Nikolić MS, Petrović R, Veljović ĐN, Ćosović V, Stanković N, Đonlagić JA. Effect of sepiolite organomodification on the performance of PCL/sepiolite nanocomposites. in European Polymer Journal. 2017;97:198-209.
doi:10.1016/j.eurpolymj.2017.10.010 .

Nikolić, Marija S., Petrović, Rada, Veljović, Đorđe N., Ćosović, Vladan, Stanković, Nadežda, Đonlagić, Jasna A., "Effect of sepiolite organomodification on the performance of PCL/sepiolite nanocomposites" in European Polymer Journal, 97 (2017):198-209,
https://doi.org/10.1016/j.eurpolymj.2017.10.010 . .

TY  - JOUR
AU  - Bjelajac, Anđelika
AU  - Đokić, Veljko R.
AU  - Petrović, Rada
AU  - Bundaleski, Nenad
AU  - Socol, Gabriel
AU  - Mihailescu, Ion N.
AU  - Rakočević, Zlatko Lj.
AU  - Janaćković, Đorđe T.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1786
AB  - A process of obtaining N-doped TiO2 nanotubes sensitized by CdS nanoparticles is presented, including detailed characterizations performed along the synthesis. Transparent TiO2 films consisting of nanotubes, 2.5 mu m long and of similar to 60 nm inner diameter, were obtained after anodization of a titanium film deposited onto FTO glass substrate. N-doping was achieved by annealing of TiO2 film in ammonia. X-ray Photoelectron Spectroscopy measurements showed that nitrogen was substitutionally incorporated in the TiO2 matrix, with the N:Ti concentration ratio of 1:100. The doping changed the optical properties of the material in such a way that the absorption edge was shifted from 380 nm to 507 nm, as observed from diffuse reflectance spectra. The influence of the microwave (MW) irradiation on the synthesized CdS quantum dots and their optical properties was investigated. It was shown that the diameter of CdS nanoparticles was increased due to releasing of S-2-ions from dimethyl sulfoxide (DMSO) as a consequence of the MW treatment. The (N)TiO2 films were then used as substrates for matrix assisted pulsed laser deposition of the CdS quantum dots with DMSO as a matrix. The laser parameters for the deposition were optimized in order to preserve the nanotubular structure open, the latter being an important feature of this type of photoanode. The structure obtained under optimized conditions has an additional absorption edge shift, reaching 603 nm.
T2  - Ceramics International
T1  - Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots
VL  - 43
IS  - 17
SP  - 15040
EP  - 15046
DO  - 10.1016/j.ceramint.2017.08.029
ER  - 

@article{
author = "Bjelajac, Anđelika and Đokić, Veljko R. and Petrović, Rada and Bundaleski, Nenad and Socol, Gabriel and Mihailescu, Ion N. and Rakočević, Zlatko Lj. and Janaćković, Đorđe T.",
year = "2017",
abstract = "A process of obtaining N-doped TiO2 nanotubes sensitized by CdS nanoparticles is presented, including detailed characterizations performed along the synthesis. Transparent TiO2 films consisting of nanotubes, 2.5 mu m long and of similar to 60 nm inner diameter, were obtained after anodization of a titanium film deposited onto FTO glass substrate. N-doping was achieved by annealing of TiO2 film in ammonia. X-ray Photoelectron Spectroscopy measurements showed that nitrogen was substitutionally incorporated in the TiO2 matrix, with the N:Ti concentration ratio of 1:100. The doping changed the optical properties of the material in such a way that the absorption edge was shifted from 380 nm to 507 nm, as observed from diffuse reflectance spectra. The influence of the microwave (MW) irradiation on the synthesized CdS quantum dots and their optical properties was investigated. It was shown that the diameter of CdS nanoparticles was increased due to releasing of S-2-ions from dimethyl sulfoxide (DMSO) as a consequence of the MW treatment. The (N)TiO2 films were then used as substrates for matrix assisted pulsed laser deposition of the CdS quantum dots with DMSO as a matrix. The laser parameters for the deposition were optimized in order to preserve the nanotubular structure open, the latter being an important feature of this type of photoanode. The structure obtained under optimized conditions has an additional absorption edge shift, reaching 603 nm.",
journal = "Ceramics International",
title = "Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots",
volume = "43",
number = "17",
pages = "15040-15046",
doi = "10.1016/j.ceramint.2017.08.029"
}

Bjelajac, A., Đokić, V. R., Petrović, R., Bundaleski, N., Socol, G., Mihailescu, I. N., Rakočević, Z. Lj.,& Janaćković, Đ. T.. (2017). Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots. in Ceramics International, 43(17), 15040-15046.
https://doi.org/10.1016/j.ceramint.2017.08.029

Bjelajac A, Đokić VR, Petrović R, Bundaleski N, Socol G, Mihailescu IN, Rakočević ZL, Janaćković ĐT. Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots. in Ceramics International. 2017;43(17):15040-15046.
doi:10.1016/j.ceramint.2017.08.029 .

Bjelajac, Anđelika, Đokić, Veljko R., Petrović, Rada, Bundaleski, Nenad, Socol, Gabriel, Mihailescu, Ion N., Rakočević, Zlatko Lj., Janaćković, Đorđe T., "Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots" in Ceramics International, 43, no. 17 (2017):15040-15046,
https://doi.org/10.1016/j.ceramint.2017.08.029 . .

TY  - JOUR
AU  - Ahribesh, Aysha Ali
AU  - Lazarevic, Slavica
AU  - Jankovic-Častvan, Ivona
AU  - Jokić, Bojan M.
AU  - Spasojević, Vojislav
AU  - Radetić, Tamara
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1349
AB  - The magnetic nanocomposites (MNCs), used as adsorbents for Cd2+ ions, were prepared by a co-precipitation method using both the untreated natural (SEP) and the partially acid-activated (ASEP) sepiolites as supports for magnetite. The synthesis conditions differed as follows: NaOH or NH3 was added in the SEP or the ASEP suspension before or after the addition of Fe3 and Fe2+. The SEP-based MNCs prepared using NaOH had a lower magnetization, but higher adsorption capacities than the MNCs synthesized using NH3. The order of the mixing of the reagents had a small influence on the properties of SEP-based MNCs, especially when NaOH was used for the synthesis. Due to acidity of the surface functional groups of the ASEP, the magnetic composite could be synthesized only when NH3 was added in the suspension of ASEP having Fe3+ and Fe2+ ions. Despite of the worse dispersibility of the magnetic particles, the adsorption capacityof the ASEP-based composite was higher than of the MNC with SEP prepared by the same procedure. All the MNCs showed a superparamagnetic behavior at room temperature and the adsorption capacities were higher than of pure compounds. The adsorption of Cd2+ on the composites was best fitted with the Sips model, which suggested the chemisorption on the heterogeneous surface at energetically non-uniform sites until a monolayer was formed. (C) 2016 Elsevier B.V. All rights reserved.
T2  - Powder Technology
T1  - Influence of the synthesis parameters on the properties of the sepiolite-based magnetic adsorbents
VL  - 305
SP  - 260
EP  - 269
DO  - 10.1016/j.powtec.2016.09.086
ER  - 

@article{
author = "Ahribesh, Aysha Ali and Lazarevic, Slavica and Jankovic-Častvan, Ivona and Jokić, Bojan M. and Spasojević, Vojislav and Radetić, Tamara and Janaćković, Đorđe T. and Petrović, Rada",
year = "2017",
abstract = "The magnetic nanocomposites (MNCs), used as adsorbents for Cd2+ ions, were prepared by a co-precipitation method using both the untreated natural (SEP) and the partially acid-activated (ASEP) sepiolites as supports for magnetite. The synthesis conditions differed as follows: NaOH or NH3 was added in the SEP or the ASEP suspension before or after the addition of Fe3 and Fe2+. The SEP-based MNCs prepared using NaOH had a lower magnetization, but higher adsorption capacities than the MNCs synthesized using NH3. The order of the mixing of the reagents had a small influence on the properties of SEP-based MNCs, especially when NaOH was used for the synthesis. Due to acidity of the surface functional groups of the ASEP, the magnetic composite could be synthesized only when NH3 was added in the suspension of ASEP having Fe3+ and Fe2+ ions. Despite of the worse dispersibility of the magnetic particles, the adsorption capacityof the ASEP-based composite was higher than of the MNC with SEP prepared by the same procedure. All the MNCs showed a superparamagnetic behavior at room temperature and the adsorption capacities were higher than of pure compounds. The adsorption of Cd2+ on the composites was best fitted with the Sips model, which suggested the chemisorption on the heterogeneous surface at energetically non-uniform sites until a monolayer was formed. (C) 2016 Elsevier B.V. All rights reserved.",
journal = "Powder Technology",
title = "Influence of the synthesis parameters on the properties of the sepiolite-based magnetic adsorbents",
volume = "305",
pages = "260-269",
doi = "10.1016/j.powtec.2016.09.086"
}

Ahribesh, A. A., Lazarevic, S., Jankovic-Častvan, I., Jokić, B. M., Spasojević, V., Radetić, T., Janaćković, Đ. T.,& Petrović, R.. (2017). Influence of the synthesis parameters on the properties of the sepiolite-based magnetic adsorbents. in Powder Technology, 305, 260-269.
https://doi.org/10.1016/j.powtec.2016.09.086

Ahribesh AA, Lazarevic S, Jankovic-Častvan I, Jokić BM, Spasojević V, Radetić T, Janaćković ĐT, Petrović R. Influence of the synthesis parameters on the properties of the sepiolite-based magnetic adsorbents. in Powder Technology. 2017;305:260-269.
doi:10.1016/j.powtec.2016.09.086 .

Ahribesh, Aysha Ali, Lazarevic, Slavica, Jankovic-Častvan, Ivona, Jokić, Bojan M., Spasojević, Vojislav, Radetić, Tamara, Janaćković, Đorđe T., Petrović, Rada, "Influence of the synthesis parameters on the properties of the sepiolite-based magnetic adsorbents" in Powder Technology, 305 (2017):260-269,
https://doi.org/10.1016/j.powtec.2016.09.086 . .

TY  - JOUR
AU  - Savić, Andrija B.
AU  - Čokeša, Đuro
AU  - Lazarevic, Slavica
AU  - Jokić, Bojan M.
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
AU  - Živković, Ljiljana
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1262
AB  - This study demonstrates that PEG-assisted hydrothermal synthesis provides a convenient and eco-friendly route to fabrication of mesoporous magnetite with enhanced capacity for phosphate removal, excellent potential for magnetic separation and good reusability. Adsorption of phosphate onto 4 laboratory prepared magnetite powders was investigated in a systematic manner. Powders were synthesized in poly(ethylene) glycol-free or assisted conditions (PEGs 400 and 20,000 at varied PEG/water ratio), and characterized in terms of crystalline structure, and magnetic, morphological, textural, and acid-base properties. PEG acted as a powerful pore forming agent, the PEG/water ratio being the key factor in developing the surface area and mesoporosity of magnetite. Uptake capacity for phosphates increased with an increase in surface area and pore volume. PEG 20,000 at a ratio of 3:1 gave the best result. This mesoporous (D-max = 11 nm), nano-scale ( LT 10 nm) magnetite was ca. 9 times more efficient than nonporous micrometric powder derived from PEG-free synthesis (Langmuir maximum capacity, q(m) = 26.2 vs. 3.0 mg g(-1)). The adsorption was pH-dependent, in accord with variations in zeta potential of magnetite. Opposite shifts of isoelectric point and point of zero charge confirmed specific adsorption of phosphates at water/magnetite interface which proceeded via replacement of surface hydroxyls and sulfates. (C) 2016 Elsevier B.V. All rights reserved.
T2  - Powder Technology
T1  - Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process
VL  - 301
SP  - 511
EP  - 519
DO  - 10.1016/j.powtec.2016.06.028
ER  - 

@article{
author = "Savić, Andrija B. and Čokeša, Đuro and Lazarevic, Slavica and Jokić, Bojan M. and Janaćković, Đorđe T. and Petrović, Rada and Živković, Ljiljana",
year = "2016",
abstract = "This study demonstrates that PEG-assisted hydrothermal synthesis provides a convenient and eco-friendly route to fabrication of mesoporous magnetite with enhanced capacity for phosphate removal, excellent potential for magnetic separation and good reusability. Adsorption of phosphate onto 4 laboratory prepared magnetite powders was investigated in a systematic manner. Powders were synthesized in poly(ethylene) glycol-free or assisted conditions (PEGs 400 and 20,000 at varied PEG/water ratio), and characterized in terms of crystalline structure, and magnetic, morphological, textural, and acid-base properties. PEG acted as a powerful pore forming agent, the PEG/water ratio being the key factor in developing the surface area and mesoporosity of magnetite. Uptake capacity for phosphates increased with an increase in surface area and pore volume. PEG 20,000 at a ratio of 3:1 gave the best result. This mesoporous (D-max = 11 nm), nano-scale ( LT 10 nm) magnetite was ca. 9 times more efficient than nonporous micrometric powder derived from PEG-free synthesis (Langmuir maximum capacity, q(m) = 26.2 vs. 3.0 mg g(-1)). The adsorption was pH-dependent, in accord with variations in zeta potential of magnetite. Opposite shifts of isoelectric point and point of zero charge confirmed specific adsorption of phosphates at water/magnetite interface which proceeded via replacement of surface hydroxyls and sulfates. (C) 2016 Elsevier B.V. All rights reserved.",
journal = "Powder Technology",
title = "Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process",
volume = "301",
pages = "511-519",
doi = "10.1016/j.powtec.2016.06.028"
}

Savić, A. B., Čokeša, Đ., Lazarevic, S., Jokić, B. M., Janaćković, Đ. T., Petrović, R.,& Živković, L.. (2016). Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process. in Powder Technology, 301, 511-519.
https://doi.org/10.1016/j.powtec.2016.06.028

Savić AB, Čokeša Đ, Lazarevic S, Jokić BM, Janaćković ĐT, Petrović R, Živković L. Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process. in Powder Technology. 2016;301:511-519.
doi:10.1016/j.powtec.2016.06.028 .

Savić, Andrija B., Čokeša, Đuro, Lazarevic, Slavica, Jokić, Bojan M., Janaćković, Đorđe T., Petrović, Rada, Živković, Ljiljana, "Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process" in Powder Technology, 301 (2016):511-519,
https://doi.org/10.1016/j.powtec.2016.06.028 . .

TY  - JOUR
AU  - Minović-Arsić, Tamara
AU  - Kalijadis, Ana
AU  - Matović, Branko
AU  - Stoiljković, Milovan
AU  - Pantić, Jelena R.
AU  - Jovanović, Jovan
AU  - Petrović, Rada
AU  - Jokić, Bojan M.
AU  - Babić, Biljana M.
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1171
AB  - Carbon cryogel/ceria composite, with 10 wt.% of ceria, was synthesized by mixing of ceria and carbon cryogel (CC). The sample was characterized by field emission scanning electron microscopy, nitrogen adsorption and X-ray diffraction. The adsorption of arsenic(III) ions from aqueous solutions on carbon cryogel/ceria nanocomposite was studied as a function of time, solution pH and As(III) ion concentration. The results are correlated with previous investigations of adsorption mechanism of arsenic(III) on carbon cryogel. Adsorption dose experiments showed that the mass of the adsorbent was reduced for 20 times, in comparison with pure CC, for the same amount of adsorbed arsenic(III) ions. BET isotherm was used to interpret the experimental data for modelling liquid phase adsorption.
T2  - Processing and Application of Ceramics
T1  - Arsenic(III) adsorption from aqueous solutions on novel carbon cryogel/ceria nanocomposite
VL  - 10
IS  - 1
SP  - 17
EP  - 23
DO  - 10.2298/PAC1601017M
ER  - 

@article{
author = "Minović-Arsić, Tamara and Kalijadis, Ana and Matović, Branko and Stoiljković, Milovan and Pantić, Jelena R. and Jovanović, Jovan and Petrović, Rada and Jokić, Bojan M. and Babić, Biljana M.",
year = "2016",
abstract = "Carbon cryogel/ceria composite, with 10 wt.% of ceria, was synthesized by mixing of ceria and carbon cryogel (CC). The sample was characterized by field emission scanning electron microscopy, nitrogen adsorption and X-ray diffraction. The adsorption of arsenic(III) ions from aqueous solutions on carbon cryogel/ceria nanocomposite was studied as a function of time, solution pH and As(III) ion concentration. The results are correlated with previous investigations of adsorption mechanism of arsenic(III) on carbon cryogel. Adsorption dose experiments showed that the mass of the adsorbent was reduced for 20 times, in comparison with pure CC, for the same amount of adsorbed arsenic(III) ions. BET isotherm was used to interpret the experimental data for modelling liquid phase adsorption.",
journal = "Processing and Application of Ceramics",
title = "Arsenic(III) adsorption from aqueous solutions on novel carbon cryogel/ceria nanocomposite",
volume = "10",
number = "1",
pages = "17-23",
doi = "10.2298/PAC1601017M"
}

Minović-Arsić, T., Kalijadis, A., Matović, B., Stoiljković, M., Pantić, J. R., Jovanović, J., Petrović, R., Jokić, B. M.,& Babić, B. M.. (2016). Arsenic(III) adsorption from aqueous solutions on novel carbon cryogel/ceria nanocomposite. in Processing and Application of Ceramics, 10(1), 17-23.
https://doi.org/10.2298/PAC1601017M

Minović-Arsić T, Kalijadis A, Matović B, Stoiljković M, Pantić JR, Jovanović J, Petrović R, Jokić BM, Babić BM. Arsenic(III) adsorption from aqueous solutions on novel carbon cryogel/ceria nanocomposite. in Processing and Application of Ceramics. 2016;10(1):17-23.
doi:10.2298/PAC1601017M .

Minović-Arsić, Tamara, Kalijadis, Ana, Matović, Branko, Stoiljković, Milovan, Pantić, Jelena R., Jovanović, Jovan, Petrović, Rada, Jokić, Bojan M., Babić, Biljana M., "Arsenic(III) adsorption from aqueous solutions on novel carbon cryogel/ceria nanocomposite" in Processing and Application of Ceramics, 10, no. 1 (2016):17-23,
https://doi.org/10.2298/PAC1601017M . .

TY  - JOUR
AU  - Albrbar, Asma Juma
AU  - Đokić, Veljko R.
AU  - Bjelajac, Anđelika
AU  - Kovač, Janez
AU  - Ćirković, Jovana
AU  - Mitrić, Miodrag
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1261
AB  - Visible-light active mesoporous N,S-doped and co-doped anatase TiO2 powders were synthesized by non-hydrolytic sol-gel route, starting from TiCl4 and Ti((OPr)-Pr-i)(4) dissolved in cyclohexane or dimethyl sulfoxide, later used as a S-doping agent. After drying in an inert atmosphere, the gels were annealed at 500 degrees C for 3 h, in air or ammonia flow, later used for N-doping. The undoped titania powder, obtained by annealing in air of the cyclohexane-based gel, was also annealed in ammonia to deduce which method is more efficient for N-doping: gel or powder annealing. The post-annealing in air after annealing in ammonia was optimized to attain the best photocatalytic activity for dye degradation under simulated visible light. The size of anatase nanocrystals decreased by doping and the specific surface area of the powders increased. The XPS analysis confirmed a successful substitution of Ti4+ by S(4+) and/or S(6+), which caused a very small band-gap narrowing. The gel annealing in ammonia was much more efficient for interstitial nitrogen incorporation in TiO2 lattice than the powder annealing. The annealing in ammonia of the gel synthesized with dimethyl sulfoxide provided the highest visible-light activity owing to high specific surface area, appropriate mesoporosity and high photoabsorption due to efficient N,S co-doping. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
T2  - Ceramics International
T1  - Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route
VL  - 42
IS  - 15
SP  - 16718
EP  - 16728
DO  - 10.1016/j.ceramint.2016.07.144
ER  - 

@article{
author = "Albrbar, Asma Juma and Đokić, Veljko R. and Bjelajac, Anđelika and Kovač, Janez and Ćirković, Jovana and Mitrić, Miodrag and Janaćković, Đorđe T. and Petrović, Rada",
year = "2016",
abstract = "Visible-light active mesoporous N,S-doped and co-doped anatase TiO2 powders were synthesized by non-hydrolytic sol-gel route, starting from TiCl4 and Ti((OPr)-Pr-i)(4) dissolved in cyclohexane or dimethyl sulfoxide, later used as a S-doping agent. After drying in an inert atmosphere, the gels were annealed at 500 degrees C for 3 h, in air or ammonia flow, later used for N-doping. The undoped titania powder, obtained by annealing in air of the cyclohexane-based gel, was also annealed in ammonia to deduce which method is more efficient for N-doping: gel or powder annealing. The post-annealing in air after annealing in ammonia was optimized to attain the best photocatalytic activity for dye degradation under simulated visible light. The size of anatase nanocrystals decreased by doping and the specific surface area of the powders increased. The XPS analysis confirmed a successful substitution of Ti4+ by S(4+) and/or S(6+), which caused a very small band-gap narrowing. The gel annealing in ammonia was much more efficient for interstitial nitrogen incorporation in TiO2 lattice than the powder annealing. The annealing in ammonia of the gel synthesized with dimethyl sulfoxide provided the highest visible-light activity owing to high specific surface area, appropriate mesoporosity and high photoabsorption due to efficient N,S co-doping. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.",
journal = "Ceramics International",
title = "Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route",
volume = "42",
number = "15",
pages = "16718-16728",
doi = "10.1016/j.ceramint.2016.07.144"
}

Albrbar, A. J., Đokić, V. R., Bjelajac, A., Kovač, J., Ćirković, J., Mitrić, M., Janaćković, Đ. T.,& Petrović, R.. (2016). Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route. in Ceramics International, 42(15), 16718-16728.
https://doi.org/10.1016/j.ceramint.2016.07.144

Albrbar AJ, Đokić VR, Bjelajac A, Kovač J, Ćirković J, Mitrić M, Janaćković ĐT, Petrović R. Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route. in Ceramics International. 2016;42(15):16718-16728.
doi:10.1016/j.ceramint.2016.07.144 .

Albrbar, Asma Juma, Đokić, Veljko R., Bjelajac, Anđelika, Kovač, Janez, Ćirković, Jovana, Mitrić, Miodrag, Janaćković, Đorđe T., Petrović, Rada, "Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route" in Ceramics International, 42, no. 15 (2016):16718-16728,
https://doi.org/10.1016/j.ceramint.2016.07.144 . .

TY  - JOUR
AU  - Bjelajac, Anđelika
AU  - Petrović, Rada
AU  - Nedeljković, Jovan
AU  - Đokić, Veljko R.
AU  - Radetić, Tamara
AU  - Ćirković, Jovana
AU  - Janaćković, Đorđe T.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/506
AB  - Ordered titania nanotubes (pore diameter approximate to 90 nm and wall thickness approximate to 10 nm) were obtained by the anodization technique and used for the ex-situ deposition of cadmium sulfide quantum dots (CdS QDs) via simple immersion of titania substrates in the CdS colloid. The colloidal dispersion of CdS nanoparticles in water was obtained in the presence of the bifunctional ligand, mercapto silane, which binds to the surface of CdS providing stability to the colloid and preventing further growth of the synthesized nanoparticles. The blue-shift of the optical absorption indicated that the CdS nanoparticles were of quantum dot size. Using the effective mass model, the average particle size was calculated to be 5.4 nm. Transmission electron microscopy provided the verification for the estimated size of the nanoparticles, which was followed by performing selected area electron diffraction to determine the mixed phase (cubic and hexagonal) of the synthesized CdS QDs. Scanning electron microscopy and reflectance spectroscopy were employed to characterize the nanostructures consisting of TiO2 nanotubes with different loadings of CdS QDs (after 24 h and 72 h immersion). It was demonstrated that mercapto silane efficiently binds CdS QDs onto TiO2 nanotubes enabling Visible-light response of the obtained nanocomposites. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
T2  - Ceramics International
T1  - Ex-situ sensitization of ordered TiO2 nanotubes with CdS quantum dots
VL  - 41
IS  - 5
SP  - 7048
EP  - 7053
DO  - 10.1016/j.ceramint.2015.02.010
ER  - 

@article{
author = "Bjelajac, Anđelika and Petrović, Rada and Nedeljković, Jovan and Đokić, Veljko R. and Radetić, Tamara and Ćirković, Jovana and Janaćković, Đorđe T.",
year = "2015",
abstract = "Ordered titania nanotubes (pore diameter approximate to 90 nm and wall thickness approximate to 10 nm) were obtained by the anodization technique and used for the ex-situ deposition of cadmium sulfide quantum dots (CdS QDs) via simple immersion of titania substrates in the CdS colloid. The colloidal dispersion of CdS nanoparticles in water was obtained in the presence of the bifunctional ligand, mercapto silane, which binds to the surface of CdS providing stability to the colloid and preventing further growth of the synthesized nanoparticles. The blue-shift of the optical absorption indicated that the CdS nanoparticles were of quantum dot size. Using the effective mass model, the average particle size was calculated to be 5.4 nm. Transmission electron microscopy provided the verification for the estimated size of the nanoparticles, which was followed by performing selected area electron diffraction to determine the mixed phase (cubic and hexagonal) of the synthesized CdS QDs. Scanning electron microscopy and reflectance spectroscopy were employed to characterize the nanostructures consisting of TiO2 nanotubes with different loadings of CdS QDs (after 24 h and 72 h immersion). It was demonstrated that mercapto silane efficiently binds CdS QDs onto TiO2 nanotubes enabling Visible-light response of the obtained nanocomposites. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.",
journal = "Ceramics International",
title = "Ex-situ sensitization of ordered TiO2 nanotubes with CdS quantum dots",
volume = "41",
number = "5",
pages = "7048-7053",
doi = "10.1016/j.ceramint.2015.02.010"
}

Bjelajac, A., Petrović, R., Nedeljković, J., Đokić, V. R., Radetić, T., Ćirković, J.,& Janaćković, Đ. T.. (2015). Ex-situ sensitization of ordered TiO2 nanotubes with CdS quantum dots. in Ceramics International, 41(5), 7048-7053.
https://doi.org/10.1016/j.ceramint.2015.02.010

Bjelajac A, Petrović R, Nedeljković J, Đokić VR, Radetić T, Ćirković J, Janaćković ĐT. Ex-situ sensitization of ordered TiO2 nanotubes with CdS quantum dots. in Ceramics International. 2015;41(5):7048-7053.
doi:10.1016/j.ceramint.2015.02.010 .

Bjelajac, Anđelika, Petrović, Rada, Nedeljković, Jovan, Đokić, Veljko R., Radetić, Tamara, Ćirković, Jovana, Janaćković, Đorđe T., "Ex-situ sensitization of ordered TiO2 nanotubes with CdS quantum dots" in Ceramics International, 41, no. 5 (2015):7048-7053,
https://doi.org/10.1016/j.ceramint.2015.02.010 . .

TY  - JOUR
AU  - Đokić, Veljko R.
AU  - Vujovic, Jelena
AU  - Marinković, Aleksandar D.
AU  - Petrovic, Rada
AU  - Janaćković, Đorđe T.
AU  - Onjia, Antonije E.
AU  - Mijin, Dušan Ž.
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5281
AB  - The photocatalytic degradation of the synthetic textile dye CI Basic Yellow 28 (BY28) in water, using a recently synthesized P160 TiO2-based catalyst, under Osram ultra-vitalux (R) lamp (300 W) light, was studied. The effects of the operational parameters, such as initial concentration of catalyst, initial dye concentration and pH, were studied. The salt effect (NaCl, Na2CO3, Na2SO4 and NaNO3) was also investigated. It was found that the optimal concentration of catalyst is 2.0 g L-1. A pseudo first-order kinetic model was illustrated using the Langmuir-Hinshelwood mechanism and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (K-By = 6.126 L mg(-1) and k(C) = 0.272 mg L-1 min(-1), respectively). The photodegradation rate was higher in weak acidic than in high acidic and alkaline conditions. The presence of CO32- ions increased the photodegradation rate while Cl-, SO42- and NO3- decreased the reaction rate. The rate of photodegradation of BY28 was measured using UV-Vis spectroscopy.
T2  - Journal of the Serbian Chemical Society
T1  - A study of the photocatalytic degradation of the textile dye CI Basic Yellow 28 in water using a P160 TiO2-based catalyst
VL  - 77
IS  - 12
SP  - 1747
EP  - 1757
DO  - 10.2298/JSC121015130D
ER  - 

@article{
author = "Đokić, Veljko R. and Vujovic, Jelena and Marinković, Aleksandar D. and Petrovic, Rada and Janaćković, Đorđe T. and Onjia, Antonije E. and Mijin, Dušan Ž.",
year = "2012",
abstract = "The photocatalytic degradation of the synthetic textile dye CI Basic Yellow 28 (BY28) in water, using a recently synthesized P160 TiO2-based catalyst, under Osram ultra-vitalux (R) lamp (300 W) light, was studied. The effects of the operational parameters, such as initial concentration of catalyst, initial dye concentration and pH, were studied. The salt effect (NaCl, Na2CO3, Na2SO4 and NaNO3) was also investigated. It was found that the optimal concentration of catalyst is 2.0 g L-1. A pseudo first-order kinetic model was illustrated using the Langmuir-Hinshelwood mechanism and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (K-By = 6.126 L mg(-1) and k(C) = 0.272 mg L-1 min(-1), respectively). The photodegradation rate was higher in weak acidic than in high acidic and alkaline conditions. The presence of CO32- ions increased the photodegradation rate while Cl-, SO42- and NO3- decreased the reaction rate. The rate of photodegradation of BY28 was measured using UV-Vis spectroscopy.",
journal = "Journal of the Serbian Chemical Society",
title = "A study of the photocatalytic degradation of the textile dye CI Basic Yellow 28 in water using a P160 TiO2-based catalyst",
volume = "77",
number = "12",
pages = "1747-1757",
doi = "10.2298/JSC121015130D"
}

Đokić, V. R., Vujovic, J., Marinković, A. D., Petrovic, R., Janaćković, Đ. T., Onjia, A. E.,& Mijin, D. Ž.. (2012). A study of the photocatalytic degradation of the textile dye CI Basic Yellow 28 in water using a P160 TiO2-based catalyst. in Journal of the Serbian Chemical Society, 77(12), 1747-1757.
https://doi.org/10.2298/JSC121015130D

Đokić VR, Vujovic J, Marinković AD, Petrovic R, Janaćković ĐT, Onjia AE, Mijin DŽ. A study of the photocatalytic degradation of the textile dye CI Basic Yellow 28 in water using a P160 TiO2-based catalyst. in Journal of the Serbian Chemical Society. 2012;77(12):1747-1757.
doi:10.2298/JSC121015130D .

Đokić, Veljko R., Vujovic, Jelena, Marinković, Aleksandar D., Petrovic, Rada, Janaćković, Đorđe T., Onjia, Antonije E., Mijin, Dušan Ž., "A study of the photocatalytic degradation of the textile dye CI Basic Yellow 28 in water using a P160 TiO2-based catalyst" in Journal of the Serbian Chemical Society, 77, no. 12 (2012):1747-1757,
https://doi.org/10.2298/JSC121015130D . .

TY  - JOUR
AU  - Jokić, Bojan M.
AU  - Mitrić, Miodrag
AU  - Radmilović, Velimir
AU  - Drmanic, Sasa
AU  - Petrović, Rada
AU  - Janaćković, Đorđe T.
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4187
AB  - High temperature hydrothermal syntheses, using calcium nitrate tetrahydrate, sodium dihydrogen phosphate and urea as precursors, and characterization of hydroxyapatite (HAp) whiskers are reported herein. The morphology and chemical composition of the crystals from a monetite to a hydroxyapatite phase were controlled by varying the starting concentrations of the precursors and the solution pH through the amount of urea that is decomposed during heating. X-ray diffraction (XRD) analysis, infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) were used to investigate the products of the syntheses in order to find the optimum reaction conditions for obtaining the desired morphology and phase composition. Different morphologies ranging from single crystals of monetite through rods and plates of hydroxyapatite with different size distribution to whisker-like single hydroxyapatite crystal were achieved by simply varying the starting concentration of urea. Structural refinement of the hydroxyapatite whiskers confirmed a strong preferential orientation along the c-axis direction of the hexagonal crystal structure, which was significantly different from the usually observed random crystal orientation. TEM and SEM analysis of the apatite whiskers confirmed single crystal structure with the a c-axis orientation parallel to the long axis of the whiskers, with sizes up to 150 mu m in length, 10 mu m in width and with a thickness of about 300 nm, that grew from the same centre of nucleation, forming flaky-like particles. (C) 2010 Elsevier Ltd and Techna Group Sri. All rights reserved.
T2  - Ceramics International
T1  - Synthesis and characterization of monetite and hydroxyapatite whiskers obtained by a hydrothermal method
VL  - 37
IS  - 1
SP  - 167
EP  - 173
DO  - 10.1016/j.ceramint.2010.08.032
ER  - 

@article{
author = "Jokić, Bojan M. and Mitrić, Miodrag and Radmilović, Velimir and Drmanic, Sasa and Petrović, Rada and Janaćković, Đorđe T.",
year = "2011",
abstract = "High temperature hydrothermal syntheses, using calcium nitrate tetrahydrate, sodium dihydrogen phosphate and urea as precursors, and characterization of hydroxyapatite (HAp) whiskers are reported herein. The morphology and chemical composition of the crystals from a monetite to a hydroxyapatite phase were controlled by varying the starting concentrations of the precursors and the solution pH through the amount of urea that is decomposed during heating. X-ray diffraction (XRD) analysis, infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) were used to investigate the products of the syntheses in order to find the optimum reaction conditions for obtaining the desired morphology and phase composition. Different morphologies ranging from single crystals of monetite through rods and plates of hydroxyapatite with different size distribution to whisker-like single hydroxyapatite crystal were achieved by simply varying the starting concentration of urea. Structural refinement of the hydroxyapatite whiskers confirmed a strong preferential orientation along the c-axis direction of the hexagonal crystal structure, which was significantly different from the usually observed random crystal orientation. TEM and SEM analysis of the apatite whiskers confirmed single crystal structure with the a c-axis orientation parallel to the long axis of the whiskers, with sizes up to 150 mu m in length, 10 mu m in width and with a thickness of about 300 nm, that grew from the same centre of nucleation, forming flaky-like particles. (C) 2010 Elsevier Ltd and Techna Group Sri. All rights reserved.",
journal = "Ceramics International",
title = "Synthesis and characterization of monetite and hydroxyapatite whiskers obtained by a hydrothermal method",
volume = "37",
number = "1",
pages = "167-173",
doi = "10.1016/j.ceramint.2010.08.032"
}

Jokić, B. M., Mitrić, M., Radmilović, V., Drmanic, S., Petrović, R.,& Janaćković, Đ. T.. (2011). Synthesis and characterization of monetite and hydroxyapatite whiskers obtained by a hydrothermal method. in Ceramics International, 37(1), 167-173.
https://doi.org/10.1016/j.ceramint.2010.08.032

Jokić BM, Mitrić M, Radmilović V, Drmanic S, Petrović R, Janaćković ĐT. Synthesis and characterization of monetite and hydroxyapatite whiskers obtained by a hydrothermal method. in Ceramics International. 2011;37(1):167-173.
doi:10.1016/j.ceramint.2010.08.032 .

Jokić, Bojan M., Mitrić, Miodrag, Radmilović, Velimir, Drmanic, Sasa, Petrović, Rada, Janaćković, Đorđe T., "Synthesis and characterization of monetite and hydroxyapatite whiskers obtained by a hydrothermal method" in Ceramics International, 37, no. 1 (2011):167-173,
https://doi.org/10.1016/j.ceramint.2010.08.032 . .

TY  - JOUR
AU  - Lazarevic, Slavica
AU  - Jankovic-Častvan, Ivona
AU  - Onjia, Antonije E.
AU  - Krstić, Jugoslav B.
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4517
AB  - Inverse gas chromatography at infinite and finite surface coverages was applied to evaluate the surface properties of an iron-modified sepiolite sorbent, Fe-sepiolite. The adsorptions of different nonpolar and polar probes were measured in the infinite-dilution regime, in the temperature range 483-513 K. For the organic probes used, the thermodynamic parameters (free energy, enthalpy, and entropy) of adsorption and the dispersive and specific components of the free energy of adsorption were determined and are discussed in terms of specific reactions that can occur on the adsorbent surface. Following the approach of Gutmann (The Donor Acceptor Approach to Molecular Interactions; Plenum Press: New York, 1978), acid/base surface characteristics were determined. The adsorption isotherms of n-hexane, benzene, chloroform, and tetrahydrofuran were used to estimate the specific surface areas, isosteric heats of adsorption, and adsorption energy distributions for the adsorption of organic molecules.
T2  - Industrial and Engineering Chemistry Research
T1  - Surface Characterization of Iron-Modified Sepiolite by Inverse Gas Chromatography
VL  - 50
IS  - 20
SP  - 11467
EP  - 11475
DO  - 10.1021/ie200595n
ER  - 

@article{
author = "Lazarevic, Slavica and Jankovic-Častvan, Ivona and Onjia, Antonije E. and Krstić, Jugoslav B. and Janaćković, Đorđe T. and Petrović, Rada",
year = "2011",
abstract = "Inverse gas chromatography at infinite and finite surface coverages was applied to evaluate the surface properties of an iron-modified sepiolite sorbent, Fe-sepiolite. The adsorptions of different nonpolar and polar probes were measured in the infinite-dilution regime, in the temperature range 483-513 K. For the organic probes used, the thermodynamic parameters (free energy, enthalpy, and entropy) of adsorption and the dispersive and specific components of the free energy of adsorption were determined and are discussed in terms of specific reactions that can occur on the adsorbent surface. Following the approach of Gutmann (The Donor Acceptor Approach to Molecular Interactions; Plenum Press: New York, 1978), acid/base surface characteristics were determined. The adsorption isotherms of n-hexane, benzene, chloroform, and tetrahydrofuran were used to estimate the specific surface areas, isosteric heats of adsorption, and adsorption energy distributions for the adsorption of organic molecules.",
journal = "Industrial and Engineering Chemistry Research",
title = "Surface Characterization of Iron-Modified Sepiolite by Inverse Gas Chromatography",
volume = "50",
number = "20",
pages = "11467-11475",
doi = "10.1021/ie200595n"
}

Lazarevic, S., Jankovic-Častvan, I., Onjia, A. E., Krstić, J. B., Janaćković, Đ. T.,& Petrović, R.. (2011). Surface Characterization of Iron-Modified Sepiolite by Inverse Gas Chromatography. in Industrial and Engineering Chemistry Research, 50(20), 11467-11475.
https://doi.org/10.1021/ie200595n

Lazarevic S, Jankovic-Častvan I, Onjia AE, Krstić JB, Janaćković ĐT, Petrović R. Surface Characterization of Iron-Modified Sepiolite by Inverse Gas Chromatography. in Industrial and Engineering Chemistry Research. 2011;50(20):11467-11475.
doi:10.1021/ie200595n .

Lazarevic, Slavica, Jankovic-Častvan, Ivona, Onjia, Antonije E., Krstić, Jugoslav B., Janaćković, Đorđe T., Petrović, Rada, "Surface Characterization of Iron-Modified Sepiolite by Inverse Gas Chromatography" in Industrial and Engineering Chemistry Research, 50, no. 20 (2011):11467-11475,
https://doi.org/10.1021/ie200595n . .

TY  - JOUR
AU  - Lazarevic, Slavica
AU  - Jankovic-Častvan, Ivona
AU  - Jovanovic, Dusan
AU  - Milonjić, Slobodan K.
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
PY  - 2007
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3206
AB  - The adsorption mechanisms of Ph2+, Cd2+ and Sr2+ ions on natural sepiolite and the influence of acid treatment on the adsorption capacity of sepiolite were investigated. The point of zero charge pH(pzc), is 7.4 +/- 0.1 for natural sepiolite and 6.9 +/- 0.1 for partially acid-activated sepiolite. The shift of the pH(pzc) of sepiolites toward lower pH values in solutions of Ph2+ and Cd2+ ions indicates that specific adsorption of these cations on natural and acid-activated sepiolites occurred, which was more pronounced for Pb2+ ions than for Cd2+ ions. There was no shift of the pH(pzc) in Solution containing Sr2+ ions, suggesting that specific adsorption of this cation did not occur. The affinity for ion exchange with the Mg2+ ions from the sepiolite structure was the highest for Pb2+ ions, then Cd2+, whereas the affinity for Sr2+ ions was negligible. The adsorption isotherms suggest that the sequence of the efficiency of the sepiolites adsorption is Ph2+ GT Cd2+ GT Sr2+. The retention of Pb2+ and Cd2+ ions by sepiolite occurs dominantly by specific adsorption and exchange of Mg2+ ions from the sepiolite structure. The concentration in the external outer sphere of the Stem layer by electrostatic forces is the dominant mechanism for the retention of Sr2+ ions on the surface of sepiolites. Despite increases in the surface areas upon acid activation, improvements in the adsorption were not observed, as a result of the decreasing number of Mg-OH groups, as main centers for specific adsorption, and the number of Mg2+ ions available for ion exchange with Pb2+, Cd2+ and Sr2+ ions. The removal of Mg-OH groups from the sepiolite also resulted in a decrease in the point of zero charge and an increase of the relative surface acidity, from 2.6 +/- 0.1 for the natural to 6.4 +/- 0.1 for the acid-activated sepiolite. (C) 2006 Elsevier B.V. All rights reserved.
T2  - Applied Clay Science
T1  - Adsorption of Pb2+, Cd2+ and Sr2+ ions onto natural and acid-activated sepiolites
VL  - 37
IS  - 1-2
SP  - 47
EP  - 57
DO  - 10.1016/j.clay.2006.11.008
ER  - 

@article{
author = "Lazarevic, Slavica and Jankovic-Častvan, Ivona and Jovanovic, Dusan and Milonjić, Slobodan K. and Janaćković, Đorđe T. and Petrović, Rada",
year = "2007",
abstract = "The adsorption mechanisms of Ph2+, Cd2+ and Sr2+ ions on natural sepiolite and the influence of acid treatment on the adsorption capacity of sepiolite were investigated. The point of zero charge pH(pzc), is 7.4 +/- 0.1 for natural sepiolite and 6.9 +/- 0.1 for partially acid-activated sepiolite. The shift of the pH(pzc) of sepiolites toward lower pH values in solutions of Ph2+ and Cd2+ ions indicates that specific adsorption of these cations on natural and acid-activated sepiolites occurred, which was more pronounced for Pb2+ ions than for Cd2+ ions. There was no shift of the pH(pzc) in Solution containing Sr2+ ions, suggesting that specific adsorption of this cation did not occur. The affinity for ion exchange with the Mg2+ ions from the sepiolite structure was the highest for Pb2+ ions, then Cd2+, whereas the affinity for Sr2+ ions was negligible. The adsorption isotherms suggest that the sequence of the efficiency of the sepiolites adsorption is Ph2+ GT Cd2+ GT Sr2+. The retention of Pb2+ and Cd2+ ions by sepiolite occurs dominantly by specific adsorption and exchange of Mg2+ ions from the sepiolite structure. The concentration in the external outer sphere of the Stem layer by electrostatic forces is the dominant mechanism for the retention of Sr2+ ions on the surface of sepiolites. Despite increases in the surface areas upon acid activation, improvements in the adsorption were not observed, as a result of the decreasing number of Mg-OH groups, as main centers for specific adsorption, and the number of Mg2+ ions available for ion exchange with Pb2+, Cd2+ and Sr2+ ions. The removal of Mg-OH groups from the sepiolite also resulted in a decrease in the point of zero charge and an increase of the relative surface acidity, from 2.6 +/- 0.1 for the natural to 6.4 +/- 0.1 for the acid-activated sepiolite. (C) 2006 Elsevier B.V. All rights reserved.",
journal = "Applied Clay Science",
title = "Adsorption of Pb2+, Cd2+ and Sr2+ ions onto natural and acid-activated sepiolites",
volume = "37",
number = "1-2",
pages = "47-57",
doi = "10.1016/j.clay.2006.11.008"
}

Lazarevic, S., Jankovic-Častvan, I., Jovanovic, D., Milonjić, S. K., Janaćković, Đ. T.,& Petrović, R.. (2007). Adsorption of Pb2+, Cd2+ and Sr2+ ions onto natural and acid-activated sepiolites. in Applied Clay Science, 37(1-2), 47-57.
https://doi.org/10.1016/j.clay.2006.11.008

Lazarevic S, Jankovic-Častvan I, Jovanovic D, Milonjić SK, Janaćković ĐT, Petrović R. Adsorption of Pb2+, Cd2+ and Sr2+ ions onto natural and acid-activated sepiolites. in Applied Clay Science. 2007;37(1-2):47-57.
doi:10.1016/j.clay.2006.11.008 .

Lazarevic, Slavica, Jankovic-Častvan, Ivona, Jovanovic, Dusan, Milonjić, Slobodan K., Janaćković, Đorđe T., Petrović, Rada, "Adsorption of Pb2+, Cd2+ and Sr2+ ions onto natural and acid-activated sepiolites" in Applied Clay Science, 37, no. 1-2 (2007):47-57,
https://doi.org/10.1016/j.clay.2006.11.008 . .