Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin

The sorption of cadmium (II) cations on the surface of amorphous macroporous silicas chemically modified with β-cyclodextrin and its functional derivatives has been studied. It was shown that sorption of cadmium (II) follows the Frendlich isotherm for heterogeneous surface. Analysis of sorption kine...

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Published in:Хімія, фізика та технологія поверхні
Date:2010
Main Authors: Belyakova, L.A., Shvets, O.M.
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Language:English
Published: Інститут хімії поверхні ім. О.О. Чуйка НАН України 2010
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Online Access:https://nasplib.isofts.kiev.ua/handle/123456789/28992
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Cite this:Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin / L.A. Belyakova, O.M. Shvets // Хімія, фізика та технологія поверхні. — 2010. — Т. 1, № 3. — С. 274-280. — Бібліогр.: 20 назв. — англ.

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author Belyakova, L.A.
Shvets, O.M.
author_facet Belyakova, L.A.
Shvets, O.M.
citation_txt Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin / L.A. Belyakova, O.M. Shvets // Хімія, фізика та технологія поверхні. — 2010. — Т. 1, № 3. — С. 274-280. — Бібліогр.: 20 назв. — англ.
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container_title Хімія, фізика та технологія поверхні
description The sorption of cadmium (II) cations on the surface of amorphous macroporous silicas chemically modified with β-cyclodextrin and its functional derivatives has been studied. It was shown that sorption of cadmium (II) follows the Frendlich isotherm for heterogeneous surface. Analysis of sorption kinetic curves in the framework of the Lagergren kinetic model for reactions of pseudo-first and pseudo-second order shows that two parallel processes take place on the surface of β-cyclodextrin-containing silicas. It has been proved that significant increasing of cadmium (II) nitrate sorption is a result of uncharged supramolecular structures formation on the surface of silicas modified with β-cyclodextrins. The chemical composition of these supramolecular structures correlates with the polarizability of functional substituents of β-cyclodextrins. Вивчено сорбцію катіонів кадмію (II) на поверхні аморфних макропористих кремнеземів, хімічно модифікованих β-циклодекстрином та його функціональними похідними. Показано, що сорбція кадмію (II) відповідає ізотермі Фрейндліха для гетерогенної поверхні. Аналіз кінетичних кривих сорбції у рамках кінетичної моделі Лагергрена для реакцій псевдопершого і псевдодругого порядку показує, що на поверхні β-циклодекстринвмісних кремнеземів відбувається два паралельні процеси. Доведено, що істотне збільшення сорбції нітрату кадмію (II) є результатом формування незаряджених супрамолекулярних структур на поверхні кремнеземів, модифікованих β-циклодекстринами. Хімічний склад цих супрамолекулярних структур корелює з поляризацією функціональних замісників β-циклодекстринів. Изучена сорбция катионов кадмия (II) на поверхности аморфных макропористых кремнеземов, химически модифицированных β-циклодекстрином и его функциональными производными. Показано, что сорбция кадмия (II) соответствует изотерме Фрейндлиха для гетерогенной поверхности. Анализ кинетических кривых сорбции в рамках кинетической модели Лагергрена для реакций псевдопервого и псевдовторого порядка показывает, что на поверхности β-циклодекстринсодержащих кремнеземов осуществляется два параллельных процесса. Доказано, что существенное увеличение сорбции нитрата кадмия (II) является результатом образования незаряженных супрамолекулярных структур на поверхности кремнеземов, модифицированных β-циклодекстринами. Химический состав этих супрамолекулярных структур коррелирует с поляризуемостью функциональных заместителей β-циклодекстринов.
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fulltext Хімія, фізика та технологія поверхні. 2010. Т. 1. № 3. С. 274–280 _____________________________________________________________________________________________ * Corresponding author belyakova@isc.gov.ua 274 ХФТП 2010. Т. 1. № 3 UDC 544.723 + 547.458.68 ADSORPTION AND COMPLEXING PROPERTIES OF SILICA MODIFIED WITH β-CYCLODEXTRIN L.A. Belyakova*, O.M. Shvets Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine 17 General Naumov Street, Kyiv 03164, Ukraine The sorption of cadmium (II) cations on the surface of amorphous macroporous silicas chemically modified with β-cyclodextrin and its functional derivatives has been studied. It was shown that sorption of cadmium (II) follows the Frendlich isotherm for heterogeneous surface. Analysis of sorption kinetic curves in the framework of the Lagergren kinetic model for reactions of pseudo-first and pseudo-second order shows that two parallel processes take place on the surface of β-cyclodextrin-containing silicas. It has been proved that significant increasing of cadmium (II) nitrate sorption is a result of uncharged su- pramolecular structures formation on the surface of silicas modified with β-cyclodextrins. The chemical composition of these supramolecular structures correlates with the polarizability of functional substituents of β-cyclodextrins. INTRODUCTION Chemical immobilization of macrocyclic or- ganic compounds capable to form inclusion com- plexes of "host–guest" type with ions and mole- cules on the surface of oxide materials is a promi- sing method for the design of active sites of extrac- tion and concentration of impurities of toxic sub- stances, and also for their chemical analysis in wa- ter and other objects of environment [1–6]. Among oxide materials highly disperse amorphous silicas possess undoubted advantages due to not only chemical, hydrolytic, thermal, and radiation resis- tances, but also in-depth studied structure and reac- tivity of its surface active centers [7–11]. The purpose of this work is to study the influ- ence of the surface structure of β-cyclodextrin- containing silicas on Cd (II) ions sorption from weakly acidic solutions. EXPERIMENTAL Highly disperse amorphous macroporous sili- ca– Silochrome C-120 with specific surface area of 118 m2 g–1, average pore diameter of 40 nm, and silanol groups concentration of 0.4 mmol g–1 was used as an initial silica adsorbent and support in the synthesis of organosilicas. Chemical immobilization of β-cyclodextrins was made on the surface of Silochrome C-120 through multi-step chemical modification (Fig. 1). Si Si O Si O Si O Si O OH OH OH Si Si O Si O O Si O Si O Si (CH2)3 NH2 OH O Si (CH2)3 NH2 adsorbent 1 adsorbent 2 Si Si O Si O O Si O Si O Si (CH2)3 NH OH O Si (CH2)3 NH2 (HO)7 (OH)7 (OH)6 Si Si O Si O O Si O Si O Si (CH2)3 NH OH O Si (CH2)3 NH2 (HO)5 (OR)6 O O Br 9 adsorbent 3 adsorbent 4 Si Si O Si O O Si O Si O Si (CH2)3 NH OH O Si (CH2)3 NH2 (HO)5 (OR)6 9 O O NH NH C NH2 S R = SO CH3 O adsorbent 5 Fig. 1. Surface structure of synthesized silica ad- sorbents Adsorption and Complexing Properties of Silica _____________________________________________________________________________________________ ХФТП 2010. Т. 1. № 3 275 Aminopropylsilica (adsorbent 2) was ob- tained by interaction of hydroxylated silica (ad- sorbent 1) with γ-aminopropyltriethoxysilane. Organosilicas chemically modified with β-cyclodextrin (β-СD) were synthesized by interac- tion of aminopropylsilica with mono- toluenesulfonyl-β-CD (adsorbent 3); bromine de- rivative of heptakis-(toluenesulfonyl)-β-CD with aminopropylsilica (adsorbent 4) and chemical interaction of bromoacetyl groups of adsorbent 4 with thiosemicarbazide (adsorbent 5). Structural and sorption parameters, chemical composition and structure of the surface layer of silica adsorbents (Table 1) were determined from the isotherms of low-temperature nitrogen ad- sorption, elemental and chemical analysis, poten- tiometric titration, thermogravimetry data, IR, UV, and 1H NMR spectroscopy. Table 1. Chemical composition of surface layer of synthesized silica adsorbents Content of chemical elements, % Adsorbent Concentration of functional groups of adsorbent, mmol g–1 H C N S Br 1 0.40 – – – – – 2 0.28 0.45 1.00 0.40 – – 3 0.035 0.70 2.80 0.40 – – 4 0.01 0.60 2.20 0.40 0.20 0.70 5 0.01 0.65 2.30 0.80 0.50 – Sorption of Cd (II) ions was studied at 22oC under static conditions using multi-batch method from 2.5⋅10–4 to 4.0⋅10–3 M (pH ~ 1) Cd(NO3)2 aqueous solutions as a function of contact time with silica and the equilibrium solution concen- tration. Suspensions containing 0.025 g of silica adsorbent and 20 cm3 of Cd(NO3)2 solution were kept for 4 h in a JULABO SW22 water thermo- stat with continuous shaking (shaking frequency 110 rpm). The amount of Cd (II) ions in the initial and equilibrium solutions was determined by the absorption band with λмах= 576 nm using xylenol orange as reagent on a Perkin Elmer Lambda 35 spectrophotometer. The relative content of various cadmium (II) species in aqueous solutions at pH 1–5 depending on the concentration of free NO3 – ions was calcu- lated using the program Chemical Equilibria in Aquatic System. Ultraviolet absorption spectra of Cd(NO3)2 aqueous solutions were recorded on a Spe- cord M-40 spectrophotometer in the wavelength range 240–400 nm in quartz cells with l = 1 cm. Infrared transmission spectra were registered in the frequency range 4000–400 cm–1 using a Thermo Nicolet NEXUS FT-IR spectrophotome- ter. To record the IR spectra samples of adsorb- ents of ~30 mg each were compacted in plates under the pressure of 108 Pa. RESULTS AND DISCUSSION From aqueous solutions of cadmium nitrate with pH ~ 1 Cd (II) ions can be adsorbed on the surface of studied silicas as two existing species: Cd2+ and Cd(NO3) +, 80% of which being divalent cation. Sorption equilibrium is achieved within 1 h, and for organosilicas 3–5 substantial sorption capacity is already realized in the first 15 minutes (Fig. 2). The isotherms of Cd (II) ions sorption for all studied functional silicas are presented in Fig. 3. 20 40 60 80 100 120 0.00 0.01 0.02 0.03 0.04 0.05 0.06 2 3 4 5 1 at / mmol g–1 t/min . Fig. 2. Effect of agitation time on sorption of Cd (II) ions by silica adsorbents 1–5 (10−3 M cad- mium (II) nitrate aqueous solution) 0.001 0.002 0.003 0 1 2 3 4 5 6 1 2 3 4 5 aeq / mmol Cd mmol–1 func. groups Ceq/mmol ml–1 Fig. 3. Isotherms of Cd (II) cations sorption for silica adsorbents 1–5 L.A. Belyakova, O.M. Shvets _____________________________________________________________________________________________ 276 ХФТП 2010. Т. 1. № 3 Adsorbents 1 and 2 practically do not absorb cations Cd (II) from solutions with a concentra- tion less than 0.001 M. The maximum sorption of Cd (II) from 0.001 M aqueous solutions over the content of chemically grafted β-CD at 1.1, 1.6, and 5.2 times for adsorbents 3–5, respectively, and the distribution coefficients increase by two orders of magnitude in comparison with that of initial silica (Table 2). Table 2. Structural and sorption parameters of silica adsorbents Adsorbent Specific surface area, m2 g–1 Specific sorption of Cd (II) cations, % Distribution coefficient, L g–1 1 118 14 7 2 111 9 5 3 98 110 125 4 90 460 200 5 85 520 340 The IR spectrum of silica 1 after adsorption of cadmium (II) is practically unchanged. In the IR spectrum of adsorbent 2 a little shift of the absorption band of the deformation vibrations of the N–H bond in the primary amino groups (1571 and 1542 cm–1) into low-frequency range (1520 cm–1) is observed, indicating the formation of a complex between aminopropyl groups and Cd (II) ions [12]. In the IR spectrum of adsorb- ent 3, besides the absorption bands belonging to the aminopropyl groups, the absorption bands of the valence vibrations of the O–H bond for seco- ndary alcohol groups (3375, 3290 cm–1) of β-CD are present. At the same time, the intensity of the valence and deformation vibrations of the C–H bonds (2950, 2880 cm–1 and 1460, 1390 cm–1 re- spectively) is higher than that for silica 2. After adsorption of cadmium (II) the absorption bands of the valence vibrations of β-CD become less pronounced, and the absorption bands of the de- formation vibrations of the N–H and C–H bonds are shifted into low-frequency region (1525, 1400, and 1325 cm–1). In the IR spectrum of ad- sorbent 4 the absorption bands of heptakis- (toluenesulfonyl)-β-CD, namely, the bands of the deformation vibrations of the O–H bond in the COH groups (1365 cm–1), the valence vibrations of the C=C bond in the benzene ring of toluene- sulfonyl groups (1490 cm–1), the characteristic absorption bands of the valence vibrations of the C=O (1755 cm–1) and C–Br bonds (680 cm–1) of the bromoacetyl groups have been registered. The absorption band at 1455 cm–1 belongs to the de- formation vibrations of the C–H bond, the ab- sorption bands at 1560 and 1540 cm–1 were at- tributed to the deformation vibrations of the N–H bonds in the amino groups. After adsorption of cadmium (II) the absorption bands of the valence vibrations of the C–H bonds become less clear, the characteristic absorption bands of the C–Br and C=O bonds of the bromoacetyl groups are absent; the absorption bands of the deformation vibrations of the N–H bond are shifted in low- frequency region (1530 cm–1). In the IR spectrum of adsorbent 5 the absorption bands of the va- lence vibrations of the C–H bond (2970, 2935, 2880 cm–1) of the methylene groups and the de- formation vibrations of the O–H bond (1635 cm–1) of the COH groups are observed. The absorption band at 1540 cm–1 corresponds to the deformation vibrations of the N–H bond in the amino groups, the absorption bands at 1470 and 1435 cm–1 were attributed to the deformation vibrations of the amino groups and the valence vibrations of the N–C–N and C=S bonds in thiosemicarbazide groups. After adsorption of cadmium (II) the absorption bands of the valence vibrations of the N–C–N and C=S bonds disappear, and the ab- sorption band of the deformation vibrations of the amino groups is shifted in low-frequency region (1520 cm–1). Hence, the side functional groups of the upper (wider) edge of β-CD mole- cule and its derivatives fixed on the surface of macroporous amorphous silica participate in the complex formation with Cd (II) ions. Increase of sorption affinity in the series adsorb- ent 3 < adsorbent 4 < adsorbent 5 correlates with chelating ligands ability [13]. The interaction of β-cyclodextrin with cad- mium (II) nitrate in a solution was studied to clari- fy the role of the inner cavity of β-cyclodextrin in the sorption of cadmium on organosilicas. The electronic spectrum of cadmium (II) nitrate solu- tion contains a symmetric absorption band with λmax = 301 nm and ε = 710 L mol–1 cm–1 which is assigned to n → π* transition of the N=O chro- mophore in nitrate-ion [14]. Upon the addition of certain amounts of β-CD to a Cd(NO3)2 solution, the absorption band at 301 nm becomes asymmet- ric and increases sharply in intensity (ε = 4000 L mol–1 cm–1). Since β-CD does not have characteristic absorption bands in the UV region, such spectral changes of the absorp- Adsorption and Complexing Properties of Silica _____________________________________________________________________________________________ ХФТП 2010. Т. 1. № 3 277 tion band of chromophore N=O show the interac- tion of NO3 – ions with β-CD, namely, the forma- tion of inclusion complex of "host–guest" type. Composition of inclusion compound was de- termined by equimolar series method. The ex- perimental data plotted in coordinates of the Benesi-Hildebrand equation [15] fall on a straight line for the complex of 1:1 (Fig. 4) (CºNO3¯ ⋅ l) / D λ = 1 / ελ + 1 / (Ks ⋅ ελ ⋅ Cºβ-CD), where Co is initial concentration of reagents (mol L–1); Dλ is optical density of equilibrium so- lutions, arbitrary units (arb. u.); ελ is molar ex- tinction coefficient of equilibrium solutions (L mol–1 cm–1); Ks is stability constant of the complex (L mol–1); l is thickness of absorbing layer of analyzed solution (cm). 1000 2000 3000 4000 5000 0,000 0,001 0,002 0,003 0,004 0,005 0,006 CοNO3 − l/Dλ, mol L−1 cm 1/ Cο β-CD, L mol−1 Fig. 4. Dependence of spectral characteristics of NO3 – on amount of β-CD in aqueous solutions in co- ordinates of the Benesi–Hildebrand equation for inclusion compound of composition 1:1 The volume of inner cavity of β-CD molecule is Vcavity β-СD = 0.262 nm3; its upper part is V½ cavity β-CD = 0.156 nm3, the volume and diameter of hydrated nitrate-ion are VNO3¯ = 0.153 nm3 and d NO3¯ = 0.67 nm, respectively [16]. Consequently, the entry of the anion into the inner cavity of β-CD is possible only through a wider edge, and loca- tion of NO3 – – in the top of β-CD torus. The sta- bility constant of complex "β-CD – NO3 – " is Ks = 1425 ± 70 L mol–1. The reason for high strength of formed inclusion complex is that the volumes of hydrated anion and upper part of in- ner cavity of β-CD are virtually identical. It has been found using chemical analysis that the interaction product of β-CD (or its bromine- and sulfur-containing derivatives) with Cd(NO3)2 contains not only nitrate-ions, but also Cd2+ in the ratio [NO3 –]:[Cd2+] = 2:1. Hence, for β-CD- containing silicas the molecular sorption of cad- mium nitrate is observed. Chemical composition of formed surface supramolecular compounds is given in Table 3. Table 3. Chemical composition of surface supra- molecular structures Functional groups of β-cyclodextrins A ds or b- en t type quantity Chemical compo- sition of supra– molecular structures (elemental analysis) 3 alcohol 21 C42H70O34 · Cd(NO3)2 4 bromoacetyl 9 C98H112O53S6Br9 · 4 Cd(NO3)2 5 thiosemicar- bazide 9 C107H148O53S15N27 · 5 Cd(NO3)2 The isotherms of cadmium (II) sorption for adsorbents 3–5 were expressed in the coordinates of the Freundlich and Langmuir equations [17, 18]. The experimental data are well fitted to lin- ear form of the Freundlich equation for adsorp- tion on heterogeneous surface (Fig. 5) log aeq = log KF + (1 / n) ⋅ log Ceq, where aeq is equilibrium sorption (mg g–1); KF is the Freundlich constant, sorption capacity (mg g–1); 1 / n is the Freundlich constant which character- izes the sorption intensity; Ceq is adsorbate equi- librium concentration in a solution (mg L–1). -5.2 -4.8 -4.4 -4.0 -1.6 -1.2 -0.8 -0.4 0.0 5 4 log Ceq/mg · L−1 log aeq/mg · g−1 3 Fig. 5. Isotherms of Cd (II) cations sorption in the Freundlich equation for adsorbents 3–5 The calculated Freundlich constants are given in Table 4. The increase of the constants KF and n in order adsorbent 3 < adsorbent 4 < adsorbent 5 is an evidence of rising contribution of side func- tional groups of immobilized β-cyclodextrins to L.A. Belyakova, O.M. Shvets _____________________________________________________________________________________________ 278 ХФТП 2010. Т. 1. № 3 Cd2+ sorption. Thus, the surface heterogeneity of adsorbents 3–5 may be due to the presence of two types of centers for sorption of Cd (II) – the inner cavity of immobilized β-CD molecules and the side alcohol, bromoacetyl, and thiosemicarbazide groups (Fig. 1). It should be taken into account that both Cd2+ and Cd(NO3) + ions can be adsorbed. Table 4. Freundlich isotherm constants n and KF for cadmium (II) cations sorption by β-cyclo- dextrin-containing silicas at 22°С Adsorbent n KF, mg · g–1 R2 3 0.80 3.90± 0.23 0.99 4 1.00 4.30 ± 0.26 0.99 5 1.25 5.50 ± 0.33 0.99 The Lagergren kinetic models [19] for processes of pseudo-first order ln (aeq – at) = ln aeq – k1t , where at and aeq are sorption (mg g–1) at time t and at equilibrium, respectively (min), k1 is rate con- stant of sorption (min–1), and pseudo-second order t / at = 1 / (k2 ⋅ aeq 2) + t / aeq , where k2 is rate constant of sorption (g⋅mg–1⋅min–1), were used for analysis of the kinetic curves of Cd (II) sorption. The kinetic curve (Fig. 6) for adsorbent 3 is linear in the coordinates of the equation for the processes of pseudo-second or- der (the rate constant of sorption k2 = 0.312 ± 0.019 g·mg–1⋅min–1, the correlation coefficient R2 = 0.99). 0 20 40 60 80 100 120 140 5 10 15 20 25 30 t · at –1 /g · mg –1 · min–1 t/min Fig. 6. Kinetic curve of Cd (II) cations sorption in the Lagergren pseudo-second order equation for adsorbent 3 It can be explained by the passing of two par- allel reactions with substantially various rates on the surface of adsorbent 3. This is the interaction of cadmium cations with inner cavity of chemi- cally fixed β-CD molecules and its side alcohol groups. This explanation seems to be quite rea- sonable, since the amount of adsorbed cad- mium (II) slightly exceeds the content of grafted β-CD (Table 2, 3). In other words, Cd (II) sorp- tion occurs mainly with participation of inner cavity of β-CD. Kinetic curves for adsorbents 4 and 5 (Fig. 7) correspond to the model of the processes of pseudo-first order (R2 = 0.99 and k1 = 1.88 ± 0.11 and 1.97 ± 0.12 min–1, respectively). 0 10 20 30 40 -1.2 -0.6 0.0 0.6 1.2 1.8 ln (aeq− at )/1 min–1 t/min 2 1 Fig. 7. Kinetic curves of Cd (II) cations sorption in the Lagergren pseudo-first order equation for ad- sorbents 4 (1) and 5 (2) It agrees well with substantial increasing of the complex formation ability of the bromoacetyl and thiosemicarbazide substituents in comparison with alcohol groups [20] (Table 3). Typical changes of IR spectra of adsorbents 1–5 after cadmium (II) sorption confirm this conclusion. Thus, the cadmium cations interact with side functional groups of β-cyclodextrin chemically grafted on the silica surface, and also with inner cavity of β-CD (through NO3 –) forming un- charged supramolecular structures on the surface of silica adsorbents. Chemical composition of these supramolecular structures correlates with polarizability of side groups of β-CD. CONCLUSIONS Interaction of Cd(NO3)2 with β-CD in a solu- tion and on the surface of highly disperse amor- phous silicas chemically modified with β-cyclo- Adsorption and Complexing Properties of Silica _____________________________________________________________________________________________ ХФТП 2010. Т. 1. № 3 279 dextrin or its bromine- and sulfur-containing functional derivatives has been studied by use of IR and UV spectroscopy, elemental and chemi- cal analysis, and also adsorption measurements. It has been shown that sorption of Cd (II) fol- lows the Freundlich isotherm for heterogeneous surface. Analysis of sorption kinetic curves in the framework of the Lagergren kinetic model for the processes of pseudo-first and pseudo- second order confirms that two parallel proc- esses take place on the surface of β-cyclo- dextrin-containing silicas. It has been proved that molecular sorption of Cd(NO3)2 is attended with the formation of supramolecular structures on the surface of β-CD-containing silicas. Chemical composition of these structures corre- lates with polarizability of functional groups of β-cyclodextrins. ACKNOWLEDGEMENTS The work is done at financial support of the European Commission (grant no. ICA2-CT- 100052), and by the Ukraine National Academy of Sciences Comprehensive Program of Funda- mental Researches "Nanostructure Systems, Nanomaterials, Nanotechnologies" (grant no. N 0103U006289). REFERENCES 1. Chen L., Zhang L.-F., Ching C.-B., Ng S.-C. Synthesis and chromatographic properties of a novel chiral stationary phase derived from heptakis(6-azido-6-deoxy-2,3-di-O-phenyl- carbamoylated)-β-cyclodextrin immobilized onto amino-functionalized silica gel via mul- tiple urea linkages // J. Chromatogr. A. – 2002. – V. 950. – P. 65–74. 2. Phan T.N.T., Bacquet M., Laureyns J., Morcellet M. New silica gels functional- ized with 2-hydroxy-3-metha- cryloyloxypropyl-β-cyclodextrin using coating or grafting methods // Phys. Chem. Chem. Phys. – 1999. – V. 1, N 22. – P. 5189–5195. 3. Liu C., Naismith N., Economy J. Advanced mesoporous organosilica material contain- ing microporous β-cyclodextrins for the removal of humic acid from water // J. Chromatogr. A. – 2004. – V. 1036. – P. 113–118. 4. Belyakova L.A., Kazdobin K.A., Belya- kov V.N. et al. Synthesis and properties of supramolecular systems based on silica // J. Colloid Interface Sci. – 2005. – V. 283, N 2. – P. 488–494. 5. Belyakov V.N., Belyakova L.A., Var- varin A.M. et al. Supramolecular structures on silica surfaces and their adsorptive proper- ties // J. Colloid Interface Sci. – 2005. – V. 285, N 1. – P. 18–26. 6. Prousoontorn M.H., Pantatan S. Produc- tion of 2-O-α-glucopyranosyl L-ascorbic acid from ascorbic acid and β-cyclodextrin using immobilized cyclodextrin glycosyl- transferase // J. Inclusion Phenom. Macro- cyclic Chem. – 2007. – V. 57, N 1–4. – P. 39–46. 7. Iler R.K. The Chemistry of Silica: Solubil- ity, Polymerization, Colloid and Surface Properties and Biochemistry of Silica. – New York: Wiley-Interscience, 1979. – 866 p. 8. Kiselev A.V., Lygin V.I. Unfrared Spectra of Surface Compounds. – New York: Wiley- Interscience, 1975. – 384 p. 9. Tertykh V.A., Belyakova L.A. Chemical Reac- tions with Participation of Silica Surface. – Kyiv: Naukova Dumka, 1991. – 261 p. (in Russian). 10. Vansant E.F., Van Der Voort P., Vran- cken K.C. Characterization and Chemical Modification on the Silica Surface. – Am- sterdam: Elsevier, 1995. –556 p. 11. Adsorption on New and Modified Inorganic Sorbents / Eds. A. Dobrowski, V.A. Ter- tykh – Amsterdam: Elsevier, 1996. – 926 p. 12. Smith A.L. Applied Infrared Spectroscopy. – New York: John Wiley and Sons, 1982. – 328 p. 13. Myasoedova G.V., Savvin S.B. Chelating Sor- bents. – Moscow: Nauka, 1984. – 172 p. (in Russian). 14. Rao C.N.R. Ultra-Violet and Visible Spec- troscopy Chemical Applications. – London: Butterworth, 1961. – 264 p. 15. Wen X., Tan F., Jing Z., Liu Z. Preparation and study the 1:2 inclusion complex of carvediol with β-cyclodextrin // J. Pharm. Biomed. Analysis. – 2004. – V. 34. – P. 517–523. 16. Chamberlain II R.V., Slowinska K., Majda M, et al. Electrostatically-induced inclusion of anions in cyclodextrin monolayers on elec- trodes // Langmuir. – 2000. – V. 16, N 3. – P. 1388–1396. L.A. Belyakova, O.M. Shvets _____________________________________________________________________________________________ 280 ХФТП 2010. Т. 1. № 3 17. Freundlich H., Heller W.J. The adsorption of cis- and trans-azobenzene // J. Am. Chem. Soc. – 1939. – V. 61, N 8. – P. 2228–2230. 18. Langmuir I. The adsorption of gases on plane surfaces of glass, mica and platinum // J. Am. Chem. Soc. – 1918. – V. 40, N 9. – P. 1361–1403. 19. Gupta S.S., Bhattacharyya K.G. Adsorption of Ni(II) on clays // J. Colloid Interface Sci. – 2006. – V. 295, N 1. – P. 21–32. 20. Pearson R.G. The theory of soft and hard ac- ids and bases // J. Chem. Educ. – 1963. – V. 45. – P. 581–587. Received 02.07.2010, accepted 17.08.2010 Адсорбційні та комплексоутворюючі властивості кремнезема, модифікованого β-циклодекстрином Л.О. Бєлякова, О.М. Швець Інститут хімії поверхні ім. О.О. Чуйка Національної академії наук України вул. Генерала Наумова 17, 03164, Київ, Україна, belyakova@isc.gov.ua Вивчено сорбцію катіонів кадмію (II) на поверхні аморфних макропористих кремнеземів, хімічно модифікованих β-циклодекстрином та його функціональними похідними. Показано, що сорбція кад- мію (II) відповідає ізотермі Фрейндліха для гетерогенної поверхні. Аналіз кінетичних кривих сорбції у рамках кінетичної моделі Лагергрена для реакцій псевдопершого і псевдодругого порядку показує, що на поверхні β-циклодекстринвмісних кремнеземів відбувається два паралельні процеси. Доведено, що істотне збільшення сорбції нітрату кадмію (II) є результатом формування незаряджених супрамо- лекулярних структур на поверхні кремнеземів, модифікованих β-циклодекстринами. Хімічний склад цих супрамолекулярних структур корелює з поляризацією функціональних замісників β-циклодекстринів. Адсорбционные и комплексообразующие свойства кремнезема, модифицированного β-циклодекстрином Л.А. Белякова, А.Н. Швец Институт химии поверхности им. А.А. Чуйко Национальной академии наук Украины ул. Генерала Наумова 17, 03164, Киев, Украина, belyakova@isc.gov.ua Изучена сорбция катионов кадмия (II) на поверхности аморфных макропористых кремнеземов, химически модифицированных β-циклодекстрином и его функциональными производными. Показано, что сорбция кадмия (II) соответствует изотерме Фрейндлиха для гетерогенной поверхности. Анализ кинетических кривых сорбции в рамках кинетической модели Лагергрена для реакций псевдопервого и псевдовторого порядка показывает, что на поверхности β-циклодекстринсодержащих кремнеземов осуществляется два параллельных процесса. Доказано, что существенное увеличение сорбции нит- рата кадмия (II) является результатом образования незаряженных супрамолекулярных структур на поверхности кремнеземов, модифицированных β-циклодекстринами. Химический состав этих супра- молекулярных структур коррелирует с поляризуемостью функциональных заместителей β-циклодекстринов.
id nasplib_isofts_kiev_ua-123456789-28992
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 2079-1704
language English
last_indexed 2025-11-29T13:54:08Z
publishDate 2010
publisher Інститут хімії поверхні ім. О.О. Чуйка НАН України
record_format dspace
spelling Belyakova, L.A.
Shvets, O.M.
2011-11-27T16:55:48Z
2011-11-27T16:55:48Z
2010
Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin / L.A. Belyakova, O.M. Shvets // Хімія, фізика та технологія поверхні. — 2010. — Т. 1, № 3. — С. 274-280. — Бібліогр.: 20 назв. — англ.
2079-1704
https://nasplib.isofts.kiev.ua/handle/123456789/28992
544.723 + 547.458.68
The sorption of cadmium (II) cations on the surface of amorphous macroporous silicas chemically modified with β-cyclodextrin and its functional derivatives has been studied. It was shown that sorption of cadmium (II) follows the Frendlich isotherm for heterogeneous surface. Analysis of sorption kinetic curves in the framework of the Lagergren kinetic model for reactions of pseudo-first and pseudo-second order shows that two parallel processes take place on the surface of β-cyclodextrin-containing silicas. It has been proved that significant increasing of cadmium (II) nitrate sorption is a result of uncharged supramolecular structures formation on the surface of silicas modified with β-cyclodextrins. The chemical composition of these supramolecular structures correlates with the polarizability of functional substituents of β-cyclodextrins.
Вивчено сорбцію катіонів кадмію (II) на поверхні аморфних макропористих кремнеземів, хімічно модифікованих β-циклодекстрином та його функціональними похідними. Показано, що сорбція кадмію (II) відповідає ізотермі Фрейндліха для гетерогенної поверхні. Аналіз кінетичних кривих сорбції у рамках кінетичної моделі Лагергрена для реакцій псевдопершого і псевдодругого порядку показує, що на поверхні β-циклодекстринвмісних кремнеземів відбувається два паралельні процеси. Доведено, що істотне збільшення сорбції нітрату кадмію (II) є результатом формування незаряджених супрамолекулярних структур на поверхні кремнеземів, модифікованих β-циклодекстринами. Хімічний склад цих супрамолекулярних структур корелює з поляризацією функціональних замісників β-циклодекстринів.
Изучена сорбция катионов кадмия (II) на поверхности аморфных макропористых кремнеземов, химически модифицированных β-циклодекстрином и его функциональными производными. Показано, что сорбция кадмия (II) соответствует изотерме Фрейндлиха для гетерогенной поверхности. Анализ кинетических кривых сорбции в рамках кинетической модели Лагергрена для реакций псевдопервого и псевдовторого порядка показывает, что на поверхности β-циклодекстринсодержащих кремнеземов осуществляется два параллельных процесса. Доказано, что существенное увеличение сорбции нитрата кадмия (II) является результатом образования незаряженных супрамолекулярных структур на поверхности кремнеземов, модифицированных β-циклодекстринами. Химический состав этих супрамолекулярных структур коррелирует с поляризуемостью функциональных заместителей β-циклодекстринов.
The work is done at financial support of the European Commission (grant no. ICA2-CT- 100052), and by the Ukraine National Academy of Sciences Comprehensive Program of Fundamental Researches "Nanostructure Systems, Nanomaterials, Nanotechnologies" (grant no. N 0103U006289).
en
Інститут хімії поверхні ім. О.О. Чуйка НАН України
Хімія, фізика та технологія поверхні
Функціоналізовані матеріали, одержані золь-гель і темплатним методами
Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
Адсорбційні та комплексоутворюючі властивості кремнезема, модифікованого β-циклодекстрином
Адсорбционные и комплексообразующие свойства кремнезема, модифицированного β-циклодекстрином
Article
published earlier
spellingShingle Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
Belyakova, L.A.
Shvets, O.M.
Функціоналізовані матеріали, одержані золь-гель і темплатним методами
title Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
title_alt Адсорбційні та комплексоутворюючі властивості кремнезема, модифікованого β-циклодекстрином
Адсорбционные и комплексообразующие свойства кремнезема, модифицированного β-циклодекстрином
title_full Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
title_fullStr Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
title_full_unstemmed Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
title_short Adsorption and Complexing Properties of Silica Modified with β-Cyclodextrin
title_sort adsorption and complexing properties of silica modified with β-cyclodextrin
topic Функціоналізовані матеріали, одержані золь-гель і темплатним методами
topic_facet Функціоналізовані матеріали, одержані золь-гель і темплатним методами
url https://nasplib.isofts.kiev.ua/handle/123456789/28992
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