DETERMINATION OF THE ACTIVATED CARBON STRUCTURAL HETEROGENEITY ON THE BASIS OF STOECKLI
AND DUBININ – STOECKLI EQUATIONS
B.J. Trznadel, P. Kowalczyk
Military Institute of Chemistry and Radiometry, 00-910 Warsaw, Poland
Activated carbons possess micropores, mesopores, and macropores. Macropores play the main role in mass transfer phenomena from gaseous phase to meso- and micropores. The presence of micropores and mesopores affects sorption properties of an adsorbent. The most important characteristic of adsorbent is pore sizes distribution, mainly micropore size distribution (MPSD). S Continue Reading »
SORPTION of URANIUM
WITH TITANUM SILICATES ZEOLITES
О.I. Zakutevsky, Т.S. Psareva, S.I. Meleshevich, N.I. Shenk,
V.А. Kanibolotsky, V.V. Strelko
Institute for Sorption and Endoecology Problems,
Ukrainian National Academy of Sciences,
General Naumov st. 13, 03680 Kyiv, Ukraine
It is known that synthetic titanium silicates zeolites are high-selection sorbents for extraction of radioisotopes of cesium and strontium from a liquid radioactive waste. The titanium silicates capacity to absorb uranium from water solutions provides an opportunity to Continue Reading »
REACTIVITY OF HYDROCHLOROSILANES ClnSi(CH3)3-nH (n=1-3) RELATIVE TO SILICA SURFACE
A.M. Varvarin, L.A. Belyakova, L.N. Kravchuk
Institute of Surface Chemistry, Ukrainian National Academy of Sciences, General Naumov st. 17, 03164 Kiev, Ukraine
Silicas modified by silicon-hydride groups (hydride silicas) are used as specific adsorbents, chromatographic supporters as well as for preparation of catalysts. The most simple method of introduction of ºSi-H groups into surface layer of silica is interaction of hydrosilanes with silicon dioxide. In order to clarify the peculiarities and the regularities of chemisorpti Continue Reading »
ON THE ACCURACY AND THE REPEATABILITY OF RESULTS OF BENZENE VAPOUR ADSORPTION MEASUREMENTS
B.J. Trznadel
Military Institute of Chemistry and Radiometry, 00-910 Warsaw, Poland
Activated carbons are structurally and energetically heterogeneous adsorbents because they possess a complex porous structure (Jankowska et al., 1991). The porous structure is usually described by the characteristic surface area, total and micropore volume and pore size distribution or energy distribution (Bansal et al., 1988). Additionally surface roughness is analysed as a structural parameter (Pfeifer and Avnir, 1983). Every porous struct Continue Reading »
INVESTIGATION OF BETA-CAROTENE ATMOSPHERIC OXIDATION PROCESS IN THE ANIONIC SURFACTANT SYSTEM IN ABSENCE AND PRESENCE OF VITAMIN C
M. Szymula
Department Radiochemistry and Colloid Chemistry, Faculty of Maria Curie-Sklodowska University, Maria Curie-Sklodowska sq. 3, 20-031 Lublin, Poland
b-Carotene is a very efficient antioxidant acting as the most important physiological quencher, which protects cells against singlet oxygen damage.
It is well known that the antioxidant activity of antioxidant substances in homogenous solutions may not be the same as that in heterogeneous media.
This matrix dependence Continue Reading »
Checked preparation of smart mesoporous silica
in acid medium
G. Tel\’biz, O. Shvets, S. Boron, O. Kochnev, V. Il\’in
Institute of Physical Chemistry, Ukrainian National Academy of Sciences,
Nauky avenue 31, 03028, Kyiv, Ukraine
The past several years have seen explosive growth in research on ordered mesoporous molecular sieves. The mesoporous material may be synthesized in any geometric form, but is preferably in the form of a film, fiber, powder or combinations thereof. Guest particles embedded in molecular sieves hosts are attracting increasing attention with respect to novel applica Continue Reading »