Institute of Sorption and Problems of Endoecology NAS of Ukraine

Kiev, Ukraine

Institute of Sorption and Problems of Endoecology NAS of Ukraine

Kiev, Ukraine
SEARCH FILTERS
Time filter
Source Type

Oleksiienko O.,Institute of Sorption and Problems of Endoecology NAS of Ukraine | Oleksiienko O.,Lappeenranta University of Technology | Levchuk I.,Lappeenranta University of Technology | Sitarz M.,AGH University of Science and Technology | And 3 more authors.
Journal of Colloid and Interface Science | Year: 2015

Titanosilicates (TiSis) were synthesized from pure and technical precursors by the sol-gel method. X-ray diffraction (XRD) studies of TiSi identified amorphous phases. The Brunauer, Emmett and Teller (BET) surface area of TiSis obtained from pure and technical precursors measured using the low-temperature nitrogen adsorption/desorption technique were 270.3 and 158.7m2g-1, respectively. Micro-mesopore and micro- meso- macropore structures were attributed to TiSi prepared from pure and technical precursors, correspondingly. TiSis mass, solution pH, contact time, initial Sr2+ concentration, temperature and background solution were investigated for their effect on sorption properties. TiSis were observed to have a high affinity for strontium in the pH range of 4-12. Strontium adsorption isotherms were established and fitted to the Langmuir, Freundlich, Redlich-Peterson, Sips and Toth models. Pseudo-first and pseudo-second models were used to describe experimental kinetic data. X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) data for TiSis were collected before and after adsorption. Heterophase was observed on the surfaces of both types of TiSi material after Sr2+ uptake. The mechanism of Sr2+ sorption on titanosilicates was suggested. © 2014 Elsevier Inc.


Oleksiienko O.,Lappeenranta University of Technology | Oleksiienko O.,Institute of Sorption and Problems of Endoecology NAS of Ukraine | Levchuk I.,Lappeenranta University of Technology | Sitarz M.,AGH University of Science and Technology | And 3 more authors.
Desalination and Water Treatment | Year: 2016

Two types of titanosilicate (TiSi) materials were synthesized by the sol–gel method using pure and technical precursors. All samples obtained were characterized using X-ray diffraction, FTIR in the mid-region and the low-temperature nitrogen adsorption/desorption technique. The synthesized xerogels were found to be amorphous with a developed porous structure. Solution pH, sample mass, initial Cs+ concentration, competitive ions, contact time and temperature were studied for their influence on TiSi sorption ability. Both samples demonstrated a high capacity for caesium across a broad pH range of 2–12, and the adsorption isotherms were fitted to the Langmuir, Freundlich, Sips, Toth and Redlich–Peterson models, while the kinetic data were described using pseudo-first and pseudo-second models. All the TiSi samples were characterized by X-ray photoelectron spectroscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy before and after the adsorption tests. Activated adsorption was proposed as a stage in the adsorption mechanism. © 2015 Balaban Desalination Publications. All rights reserved.


Oleksiienko O.,Institute of Sorption and Problems of Endoecology NAS of Ukraine | Oleksiienko O.,Lappeenranta University of Technology | Meleshevych S.,Institute of Sorption and Problems of Endoecology NAS of Ukraine | Strelko V.,Institute of Sorption and Problems of Endoecology NAS of Ukraine | And 7 more authors.
RSC Advances | Year: 2015

A modified approach using the sol-gel synthesis of titanosilicate (TiSi) with a developed pore structure under relatively mild synthesis conditions was developed. To identify the controlling factors for the preparation of gels with the desired properties, the influences of the synthesis parameters on the structure and sorption capacity of the materials were studied. The chosen synthesis conditions allowed the preparation of TiSi xerogels with a high decontamination factor for both Sr2+ and Cs+. Effects of competitive ions on the separation factors, distribution and selectivity coefficients were studied from different background solutions containing Sr2+ and Cs+ simultaneously. It could be shown that it is possible to produce TiSi gels with developed pore structures that are capable of removing Sr2+ and Cs+ from complex aqueous solutions. This journal is © The Royal Society of Chemistry.


PubMed | Institute of Sorption and Problems of Endoecology NAS of Ukraine, AGH University of Science and Technology and Lappeenranta University of Technology
Type: | Journal: Journal of colloid and interface science | Year: 2014

Titanosilicates (TiSis) were synthesized from pure and technical precursors by the sol-gel method. X-ray diffraction (XRD) studies of TiSi identified amorphous phases. The Brunauer, Emmett and Teller (BET) surface area of TiSis obtained from pure and technical precursors measured using the low-temperature nitrogen adsorption/desorption technique were 270.3 and 158.7 m(2) g(-1), respectively. Micro-mesopore and micro- meso- macropore structures were attributed to TiSi prepared from pure and technical precursors, correspondingly. TiSis mass, solution pH, contact time, initial Sr(2+) concentration, temperature and background solution were investigated for their effect on sorption properties. TiSis were observed to have a high affinity for strontium in the pH range of 4-12. Strontium adsorption isotherms were established and fitted to the Langmuir, Freundlich, Redlich-Peterson, Sips and Toth models. Pseudo-first and pseudo-second models were used to describe experimental kinetic data. X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) data for TiSis were collected before and after adsorption. Heterophase was observed on the surfaces of both types of TiSi material after Sr(2+) uptake. The mechanism of Sr(2+) sorption on titanosilicates was suggested.

Loading Institute of Sorption and Problems of Endoecology NAS of Ukraine collaborators
Loading Institute of Sorption and Problems of Endoecology NAS of Ukraine collaborators