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1.
Инвентарный номер: нет.
   
   N 10


   
    N-(2-(2-pyridyl)ethyl)chitosan: synthesis, characterization and sorption properties [Text] / S. YU. Bratskaya, Yu. A. Azarova, E. G. Matochkina, M. I. Kodess, Yu. G. Yatluk, A. V. Pestov // Carbohydrate Polymers. - 2011. - In Press, Accepted Manuscript, Availabe online 31 Augist 2011
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: The method of producing N-2-(2-pyridyl)ethylchitosan (PE-chitosan) with substitution degrees (DS) up to 1.2 has been developed using the “synthesis in gel” approach for direct addition reaction between 2-vynilpyridine and chitosan. Investigation of sorption properties has revealed significantly higher affinity of pyridylethyl fragments to Pt(IV)) and Pd(II) ions compared to the unsubstituted amino groups of chitosan. The maximum sorption capacities of PE-chitosan in 0.1 M HCl solution were estimated as 5.56 mmol/g for Au(III), 3.67 mmol/g for Pd(II), and 2.75 mmol/g for Pt(IV). Sorption capacities of PE-chitosan for transition metal ions at pH 4-8 were 1.5-2.6 higher than those of chitosan with the highest values attained for Cu(II) and Ag(I) ions–1.50 mmol/g and 1.53 mmol/g, respectively. The PE-chitosan application for preconcentration of Au(III) with subsequent elution with HCl/thiourea mixtures was proved to be efficient for atomic absorption spectroscopy analysis of multi-component solutions with low gold content

\\\\Expert2\\nbo\\Carbohydrate Polymers\\2011, Article inPress, 31 August.pdf
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2.
Инвентарный номер: нет.
   
   S 73


   
    Sorbents based on modified polysiloxanes [Text] / L. K. Neudachina, A. Y. Golub, Yu. G. Yatluk, V. A. Osipova, Yu. A. Berdugin, E. M. Gorbunova, L. V. Adamova, O. V. Koryakova, M. V. Kuznetsov // Inorganic Materials. - 2011. - Vol. 47, № 4. - P435-441 : ил. - Bibliogr. : p. 441 (15 ref.)
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: Organic-inorganic hybrid sorbents based on a polysiloxane modified with amino and thiourea groups have been synthesized for the first time by a sol-gel process. The structure of the sorbents has been determined by X-ray photoelectron spectroscopy and IR spectroscopy. Their thermal stability has been assessed and the mechanism of their degradation has been elucidated. The structural and adsorption parameters of the sorbents have been evaluated. The results demonstrate that the introduction of amino groups into the structure of the polysiloxane yields an effective sorbent for Pb(II) extraction and enables Cu(II) and Zn(II) separation from Co(II) and Ni(II). The thiourea-modified polysiloxane selectively sorbs Bi(III) (0.1-2 M HCl), Pt(IV) (pH 2), and Pb(II) (pH 3). Divalent Co, Ni, Cu, and Zn can be sorbed from alkaline solutions

\\\\Expert2\\nbo\\Inorganic Materials\\2011, v.47, N 4, p. 435.pdf
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3.
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   N 10


   
    N-(2-(2-Pyridyl)ethyl)chitosan (PEC) for Pd(II) and Pt(IV) sorption from HCl solutions [Text] / L. A. Santos Sorena, M. Ruiz, A. V. Pestov, A. M. Sastre, Yu. G. Yatluk, E. Guibal // Cellulose. - 2011. - Vol. 18, № 2. - P309-325. - Bibliogr. : p. 324-325 (32 ref.)
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: Chitosan was modified by grafting 2-pyridyl-ethyl moieties on the biopolymer backbone for the synthesis of a Platinum Group Metal (PGM) sorbent. The sorbent was tested for Pd(II) and Pt(IV) sorption from HCl solutions. Stable for HCl concentrations below 0.5 M, the sorbent reached sorption capacities as high as 3.2 and 2.6 mmol metal g?1 for Pd(II) and Pt(IV), respectively. Metal sorption mainly proceeds by electrostatic attraction in acidic solutions, though a contribution of complexation mechanism cannot be totally rejected. The resistance to intraparticle diffusion is the main controlling mechanism for uptake kinetics. While agitation speed has a limited effect on kinetics, metal concentration and sorbent dosage have a greater effect on the kinetic profiles. The intraparticle diffusivity varies between 3 ? 10?11 and 4.5 ? 10?10 m2 min?1. Thiourea (combined with HCl solution) is used for Pd(II) and Pt(IV) desorption. The resin could be desorbed and recycled for a minimum of five cycles maintaining high efficiencies of sorption and desorption

\\\\Expert2\\nbo\\Cellulose\\2011, v.18, p. 309.pdf
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4.
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    2,3-Epoxyperfluoro-2-methylpentane in reactions with urea and thiourea [Electronic resource] / T. I. Filyakova, V. I. Saloutin, A. Ya. Zapevalov, P. A. Slepukhin, M. I. Kodess, V. I. Saloutin // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2011. - Vol. 47, № 5. - P650-658 : рис., табл. - Bibliogr. : p. 658 (24 ref.)
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: 2,3-Epoxyperfluoro-2-methylpentane reacts with thiourea in protic (methanol, 2-propanol) and aprotic (dioxane) solvents, and also with urea in acetonitrile affording unexpected products: 1-(2,2,3,3,3-pentafluoropropionyl)-2-(2,2,2-trifluoro-1-trifluoro-methylethyl)isothiourea, and 1-(2,2,3,3,3-pentafluoropropionyl)-3-(2,2,2-trifluoro-1-trifluoro-methylethyl)urea respectively that result from the rearrangement of the intermediately formed ketone in the process of the intramolecular “haloform” cleavage. At the same time in dioxane the 2,3-epoxyperfluoro-2-methylpentane reacts with urea with the formation of a heterocyclic compound, 2-amino-4-pentafluoroethyl-5,5-bis(trifluoromethyl)-4,5-dihydrooxazol-4-ol. From 1-(2,2,3,3,3-pentafluoropropionyl)-2-(2,2,2-trifluoro-1-trifluoromethylethyl)isothiourea and Cu(OAc)2 a stable fluorine-containing chelate complex was obtained

\\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2011, 47 (5), 650-658.pdf
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5.
Инвентарный номер: нет.
   
   R 31


   
    Recyclization of isopropyl 2-(1-aryl-4,5-dioxo-2-phenyl-4,5-dihydro-1H-pyrrol-3-yl)-2-oxoacetates by the action of thiourea [Electronic resource] / M. V. Dmitriev, P. S. Silaichev, P. A. Slepukhin, A. N. Maslivets // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2011. - Vol. 47, № 4. - P627-629. - Bibliogr. : p. 629 (3 ref.)
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ

\\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2011, 47 (4), 627-629.pdf
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6.
Инвентарный номер: нет.
   
   N 10


   
    N-(2-(2-Pyridyl)ethyl)chitosan (PEC) for Pd(II) and Pt(IV) sorption from HCl solutions / L. A. Santos Sorena, M. Ruiz, A. V. Pestov, A. M. Sastre, Yu. G. Yatluk, E. Guibal // Cellulose. - 2011. - Vol. 18, № 2. - С. 309-325
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Кл.слова (ненормированные):
CHITOSAN – PYRIDYL GROUPS -- PALLADIUM -- PLATINUM
Аннотация: Chitosan was modified by grafting 2-pyridyl-ethyl moieties on the biopolymer backbone for the synthesis of a Platinum Group Metal (PGM) sorbent. The sorbent was tested for Pd(II) and Pt(IV) sorption from HCl solutions. Stable for HCl concentrations below 0.5 M, the sorbent reached sorption capacities as high as 3.2 and 2.6 mmol metal g?1 for Pd(II) and Pt(IV), respectively. Metal sorption mainly proceeds by electrostatic attraction in acidic solutions, though a contribution of complexation mechanism cannot be totally rejected. The resistance to intraparticle diffusion is the main controlling mechanism for uptake kinetics. While agitation speed has a limited effect on kinetics, metal concentration and sorbent dosage have a greater effect on the kinetic profiles. The intraparticle diffusivity varies between 3 ? 10?11 and 4.5 10?10 m2 min?1. Thiourea (combined with HCl solution) is used for Pd(II) and Pt(IV) desorption. The resin could be desorbed and recycled for a minimum of five cycles maintaining high efficiencies of sorption and desorption. ??

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7.
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    Development of a method for the thiocarbamoylation of polyepichlorohydrin with a high degree of functionalization / A. P. Rodionova, A. V. Mekhaev, O. V. Koryakova [et al.] // Russian chemical bulletin. - 2021. - Vol. 70, № 6. - P1167-1173
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Кл.слова (ненормированные):
POLYEPICHLOROHYDRIN -- THIOUREA -- SYNTHESIS IN GEL
Аннотация: The conditions for the homogeneous functionalization of polyepichlorohydrin (PECH) with thiourea by the “synthesis in gel” method were experimentally selected. The best solvent for this process is 1,4-dioxane. The reaction mixture visually represents a physical gel in the range of polymer concentrations from 6 to 20%. The composition of the products was characterized by the data of elemental analysis, and specific features of their structure were established using FT-IR spectroscopy and thermogravimetry with the simultaneous IR spectrometric identification of the decomposition products. Thiourea was shown to react with PECH as an ambident nucleophile with the formation of both groups of N-substituted thiourea and fragments of isothiuronium salt. The total degree of functionalization was 90%. The crosslinking of the macromolecules proceeds simultaneously due to which the obtained products with different degrees of functionalization are insoluble in organic solvents. The thiocarbamoylated PECH derivative demonstrates antiselectivity to CuII ions in the sorption of the metal ions of the Irving—Williams series.

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8.
Инвентарный номер: нет.
   


   
    Stereoselective synthesis of dihydropyrimidinethione podand in the presence of L-proline or 4-hydroxy-L-proline and metal nitrates / E. S. Filatova, O. V. Fedorova, I. G. Ovchinnikova [et al.] // Russian chemical bulletin. - 2022. - Vol. 71, № 7. - P1506-1513
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: The asymmetric Biginelli reaction involving a 3-oxobutanoyl-containing podand, benzaldehyde, and thiourea was studied using secondary amines as a chiral inductor, Brönsted acid as a catalyst, and metal salts (especially metal nitrates) as an additive of asymmetric catalysis (AAC) was studied. The tuberculostatically active dihydropyrimidine-thione-containing podand was synthesized with an enantiomeric excess of 57% in the presence of 4-hydroxy-L-proline. In the presence of metal nitrates, the influence of the ionic radius of the cation on the enantioselective excess of the reaction under study was observed, which made it possible to propose a possible mechanism of chiral induction controlled by the complexing ability of the initial β-ketoester-containing podand with metal ions and coordination of the reagents in the transition states.

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9.
Инвентарный номер: нет.
   
   Т 42


   
    Тиокарбамоилированные производные полиаминов для сорбционного извлечения золота, серебра и ртути из растворов тиосульфатного выщелачивания / Ю. О. Привар [и др.] // Природные опасности, современные экологические риски и устойчивость экосистем: VII Дружининские чтения: материалы Всероссийской научной конференции с международным участием. - Хабаровск : ОмегаПресс, 2018. - С. 75-79
ББК 24
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: We have suggested a one-step method for the synthesis of thi-ocarbamoyl derivatives of polyallylamine (TСPAA) and polyaminostyrene (TСPAS) in the eutectic melt thiourea/ammonium thiocyanate, that is more safe and simple in comparison with the known method of functionalization using carbon disulfide. The resulting derivatives are insoluble and can be used as sor-bents without additional cross-linking. Sorption properties of TCPAA and TCPAS toward gold, silver and mercury ions have been studied in solutions of ammonia-thiosulfate leaching of gold and silver-containing sludge of Chalgan experimental workshop, which are also contaminated with mercury. It was shown that both TCPAA and TCPAS are efficient sorbents for silver, while ef-fective recovery of gold and mercury is achieved only with low- and medium-substituted TCPAA.

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10.
Инвентарный номер: нет.
   
   N 10


   
    N-(2-(2-pyridyl)ethyl)chitosan: Synthesis, characterization and sorption properties / S. YU. Bratskaya, Yu. A. Azarova, E. G. Matochkina, M. I. Kodess, Yu. G. Yatluk, A. V. Pestov // Carbohydrate Polymers. - 2012. - Vol. 87, № 1. - С. 869-875
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Кл.слова (ненормированные):
CHITOSAN N-HETEROCYCLIC DERIVATIVES -- SELECTIVE ADSORPTION -- PYRIDINE DERIVATIVES
Аннотация: The method of producing N-2-(2-pyridyl)ethylchitosan (PE-chitosan) with substitution degrees (DS) up to 1.2 has been developed using the "synthesis in gel" approach for direct addition reaction between 2-vynilpyridine and chitosan. Investigation of sorption properties has revealed significantly higher affinity of pyridylethyl fragments to Pt(IV)) and Pd(II) ions compared to the unsubstituted amino groups of chitosan. The maximum sorption capacities of PE-chitosan in 0.1 M HCl solution were estimated as 5.56 mmol/g for Au(III), 3.67 mmol/g for Pd(II), and 2.75 mmol/g for Pt(IV). Sorption capacities of PE-chitosan for transition metal ions at pH 4-8 were 1.5-2.6 higher than those of chitosan with the highest values attained for Cu(II) and Ag(I) ions - 1.50 mmol/g and 1.53 mmol/g, respectively. The PE-chitosan application for preconcentration of Au(III) with subsequent elution with HCl/thiourea mixtures was proved to be efficient for atomic absorption spectroscopy analysis of multi-component solutions with low gold content

\\\\Expert2\\nbo\\Carbohydrate Polymers\\2012, v. 87, p.869.pdf
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11.
Инвентарный номер: нет.
   
   T 44


   
    Thermal stability of new sorption materials based on polysiloxanes / L. K. Neudachina, A. Y. Golub, E. M. Gorbunova, Yu. G. Yatluk // Glass Physics and Chemistry. - 2011. - Vol.37, №6. - С. 603-612
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Кл.слова (ненормированные):
THERMAL STABILITY -- THIOCARBAMOYLATED POLYSILOXANES -- SILOXANE MATRIX
Аннотация: The thermal stability of the unmodified, aminated, and thiocarbamoylated polysiloxanes has been studied. The siloxane matrix is stable in the temperature range up to 800°C. For the first time, mass spectrometry has been applied to the analysis of the composition of the gaseous products of thermal decomposition of the studied polysiloxanes. It has been shown that, in the process of thermal decomposition, the terminal functional groups are detached and oxidized. Water, ammonia, nitrogen, carbon, and sulfur (in the case of thiourea-modified sorbent) oxides are formed predominantly. The quantitative removal of functional groups during heating up to 800°C has been confirmed by IR spectroscopy. A mechanism of thermal decomposition of polysiloxane xerogels has been proposed. It has been found that adsorption of platinum increases the thermal stability of the samples

\\\\Expert2\\nbo\\Glass Physics and Chemistry\\2011, V. 37, N 6, P.603-612.pdf
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12.
Инвентарный номер: нет.
   
   P 17


   
    Palladium and platinum sorption on a thiocarbamoyl-derivative of chitosan [Text] / A. Butewicz, K. Campos Galivan, A. V. Pestov, Yu. G. Yatluk, A. W. Trochimczuk, E. Guibal // Journal of Applied Polymer Science . - 2010. - Vol. 116, № 6. - P3318-3330 : рис.
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: Immobilizing thiourea onto chitosan allowed using the polymer for the recovery of platinum groups metals (PGMs) in acidic solutions (up to 1–2M HCl concentrations). At low HCl concentration protonated amine groups may sorb chloroanionic metal species (electrostatic attraction mechanism); however, most of sorption proceeds through chelation on sulfur containing groups (less sensitive to acidic conditions). The bi-site Langmuir equation was used for fitting sorption isotherms. The sorption of PGMs was weakly affected by the composition of the solution (presence of high concentration of anions and base metals). Maximum sorption capacities for Pd(II) and Pt(IV) ranged between 274 and 330 mg g?1 in 0.25M HCl solutions and decreased to 150–198 mg g?1 in 2M HCl solutions: Pd(II) sorption was systematically higher than Pt(IV) sorption. The pseudo-second rate equation was used for modeling the uptake kinetics. Agitation speed hardly affected uptake kinetics indicating that external diffusion resistance is not the rate controlling step. Desorption yield higher than 85% were obtained using thiourea in 0.1M HCl solution. The adsorbents could be reused for at least three cycles

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13.
Инвентарный номер: нет.
   
   S 98


   
    Syntheses of novel 4-polyfluoroalkyl-substituted 5,6-oligomethylene pyrimidines [Text] / D. V. Sevenard, O. G. Khomutov, O. V. Koryakova, V. V. Sattarova, M. I. Kodess, J. Stelten, I. Loop, E. Lork, K. I. Pashkevich, G. -V. Roeschenthaler // Synthesis. - 2000. - № 12. - P1738-1748
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: 2-Acylcycloalkanones having polyfluoroalkyl groups react with guanidine, urea, thiourea, methylisothiourea, benzamidine, guanylthiourea, dicyanodiamide, and trifluoroacetylurea by Lewis-acid catalysis to form the corresponding 5,6-oligomethylene pyrimidines. A decrease in the yields along with increase of polyflyoroalkyl substituent length in the molecule of the starting 1,3-diketone was observed in the case of reagents with lower nucleophilicity (urea, thiourea, dicyanodiamide). The pyrimidines obtained from aromatic aldehydes showed E-configuration with respect to the arylidene double bond. Tautomeric structures as a function of the substituent in 2 position in the pyrimidine ring both in liquid and solid state were investigated by X-ray diffraction, IR and NMR spectroscopy.

\\\\expert2\\nbo\\Synthesis\\2000, № 12. p.1738.pdf
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14.
Инвентарный номер: нет.
   
   P 80


   
    Polyfluoroalkylated 1,3-thiazolines: synthesis from polyfluoro-2,3-epoxyalkanes [Text] / L. V. Saloutina, A. Ya. Zapevalov, M. I. Kodess, V. I. Saloutin, G. G. Aleksandrov, O. N. Chupakhin // Journal of Fluorine Chemistry. - 2000. - Vol. 104, № 2. - P155-165
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: The interaction of polyfluoro-2,3-epoxyalkanes with thiourea and thiosemicarbazide results in 2-amino-5-fluoro-4-hydroxy-4,5-di(polyfluoroalkyl)-1,3-thiazolines and 5-fluoro-2-hydrazino-4-hydroxy-4,5-di(polyfluoroalkyl)-1,3-thiazolines, respectively. Asymmetric oxiranes yield mixtures of regioisomers, and the ring opening has been found to occur mainly near the bulkier fluoroalkyl group. The reaction with thiourea proceeds stereospecifically in dimethyl sulfoxide. The molecular structure of E-isomers of 2-amino-5-fluoro-4-hydroxy-4,5-bis(trifluoromethyl)-1,3-thiazoline and 2-amino-5-fluoro-5-heptafluoropropyl-4-hydroxy-4-trifluoromethyl-1,3-thiazoline has been established by X-ray crystallography.????

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15.
Инвентарный номер: нет.
   
   R 30


   
    Reactions of alkyl 2-benzylidene-2-polyfluoroacylacetates with N,N-dinucleophiles [Electronic resource] / M. V. Pryadeina, Ya. V. Burgart, M. I. Kodess, V. I. Saloutin, O. N. Chupakhin // Russian Chemical Bulletin (Translation of Izvestiya Akademii Nauk, Seriya Khimicheskaya). - 2004. - Vol. 53, № 6. - P1261-1266. - Библиогр. : с. 1266 (16 назв.)
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: Alkyl 2-benzylidene-2-polyfluoroacylacetates react with urea and thiourea to yield 5-ethoxycarbonyl-4-fluoroalkyl-4-hydroxy-6-phenylhexahydropyrimidin-2-ones and -2-thiones and with guanidine sulfate to form 2-amino-5-ethoxycarbonyl-4-fluoroalkyl-6-phenyl-1,6-dihydropyrimidines and 3,6-diethoxycarbonyl-2,7-difluoroalkyl-4,5-diphenyl-4,5-dihydro-1H-pyrido[1,2-a]pyrimidines, and they react with phenylhydrazine to afford 4-alkoxycarbonyl-3-fluoroalkyl-3-hydroxy-1,5-diphenylpyrazolidines. Hydrazine hydrate catalyzes the formation of 3,5-diethoxycarbonyl-2,6-difluoroalkyl-2,6-dihydroxy-4-phenyltetrahydropyrans. When treated with anhydrous hydrazine and o-phenylenediamine, these esters cleave to form the products of condensation of fluoroacyl ester and benzaldehyde with diamines.

\\\\Expert2\\nbo\\Russian Chemical Bulletin\\2004, 53 (6), 1261-1266.pdf
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16.
Инвентарный номер: нет.
   
   A 10


   
    A route to fluorocontaining 1,3-thiazolines via internal polyfluorooxiranes [Electronic resource] / L. V. Saloutina, A. Ya. Zapevalov, M. I. Kodess, V. I. Saloutin, O. N. Chupakhin // Mendeleev Communications. - 1999. - N 6. - P231-232 . - ISSN 0959-9436
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: The reaction of internal fluoroolefin oxides with thiourea results in 2-amino-5-fluoro-4-hydroxy-4,5-di(polyfluoroalkyl)-1,3-thiazolines, providing a route to an unknown type of fluorine-containing thiazolines with two fluoroalkyl substituents

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17.
Инвентарный номер: нет.
   
   O-57


   
    One-step solvent-free synthesis of fluoroalkyl-substituted 4-hydroxy-2-oxo(thioxo)hexahydropyrimidines in the presence of 1-butyl-3-methylimidazolium tetrafluoroborate [Electronic resource] / E. S. Putilova, N. A. Troitskii, S. G. Zlotin, O. G. Khudina, Ya. V. Burgart, V. I. Saloutin, O. N. Chupakhin // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 9. - P1392-1395
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: A convenient procedure has been developed for the synthesis of fluoroalkyl-substituted 6-aryl-4-hydroxy-2-oxo-(thioxo)hexahydropyrimidine derivatives by three-component condensation of fluorinated ?-dicarbonyl compounds with aromatic aldehydes and urea or thiourea in the absence of a solvent using 6 mol % of 1-butyl-3-methylimidazolium tetrafluoroborate as catalyst.

\\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (9), 1392.pdf
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18.
Инвентарный номер: нет.
   
   M 57


   
    Mercury sorption on a thiocarbamoyl derivative of chitosan [Text] / K. C. Gavilan, A. V. Pestov, H. M. Garcia, Yu. G. Yatluk, J. Roussy, E. Guibal // Journal of Hazardous Materials. - 2009. - Vol. 165, № 1-5. - P415-426
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: The grafting of thiourea on chitosan backbone allows synthesizing a thiocarbamoyl derivative that was very efficient for mercury sorption in acidic solutions. Though the sorption capacity is not increased compared to raw chitosan in near neutral solutions, this modification allowed maintaining high sorption capacity (close to 2.3 mmol Hg g-1) at pH 2. Mercury sorption in acidic solutions is not affected by the presence of competitor metals (such as Zn(II), Pb(II), Cu(II), Cd(II), Ni(II)) or the presence of nitrate anions (even at concentration as high as 0.8 M)). The presence of chloride or sulfate anions (0.8 M) decreased Hg(II) sorption capacity to 1 mmol Hg g-1. Kinetics are controlled by a combination of pseudo second-order reaction rate and resistance to intraparticle diffusion. Mercury desorption reached about 75% using thiourea (in HCl solution)

\\\\Expert2\\nbo\\Journal of Hazardous Materials\\2009, v.165.p.415.pdf
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19.
Инвентарный номер: нет.
   
   N 10


   
    N-(2-(2-Pyridyl)ethyl)chitosan (PEC) for Pd(II) and Pt(IV) sorption from HCl solutions [] / L. A. Santos Sorena, M. Ruiz, A. V. Pestov, A. M. Sastre, Yu. G. Yatluk, E. Guibal // Cellulose. - 2010. - 6 December. - Online first : рис., табл.
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Аннотация: Chitosan was modified by grafting 2-pyridyl-ethyl moieties on the biopolymer backbone for the synthesis of a Platinum Group Metal (PGM) sorbent. The sorbent was tested for Pd(II) and Pt(IV) sorption from HCl solutions. Stable for HCl concentrations below 0.5 M, the sorbent reached sorption capacities as high as 3.2 and 2.6 mmol metal g1 for Pd(II) and Pt(IV), respectively. Metal sorption mainly proceeds by electrostatic attraction in acidic solutions, though a contribution of complexation mechanism cannot be totally rejected. The resistance to intraparticle diffusion is the main controlling mechanism for uptake kinetics. While agitation speed has a limited effect on kinetics, metal concentration and sorbent dosage have a greater effect on the kinetic profiles. The intraparticle diffusivity varies between 3 10?11 and 4.5 1010 m2 min1. Thiourea (combined with HCl solution) is used for Pd(II) and Pt(IV) desorption. The resin could be desorbed and recycled for a minimum of five cycles maintaining high efficiencies of sorption and desorption

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20.
Инвентарный номер: нет.
   
   T 45


   
    Thiocarbamoyl chitosan as a novel sorbent with high sorption capacity and selectivity for the ions of gold(III), platinum(IV), and palladium [Electronic resource] / A. V. Pestov, S. Yu. Bratskaya, A. Slobodyuk, V. A. Avramenko, Yu. G. Yatluk // Russian Chemical Bulletin (Translation of Izvestiya Akademii Nauk, Seriya Khimicheskaya). - 2010. - Vol. 59, № 7. - P1303-1306
ББК 54
Рубрики: ХИМИЧЕСКИЕ НАУКИ
Кл.слова (ненормированные):
CHITOSAN -- THIOCARBAMOYL CHITOSAN -- IONS OF GOLD(III)
Аннотация: Thiocarbamoyl chitosan (TCC) was synthesized by grafting thiourea on chitosan backbone in eutectic composition of ammonium thiocyanate—thiourea. Insoluble products with the amno group functionalization degree of 0.3–1.1 can be prepared by varying the conditions of polymer-analogous (synthesis in a gel) transformation. Structure of the synthesized chitosan derivatives was characterized by elemental analysis, diffuse reflectance infrared spectroscopy, and the solid state 13C NMR. Study of sorption properties of TCC shows high sorption capacity and selectivity for the ions of gold(III), platinum(IV), and palladium(II) as evidenced by results obtained at pH 2 in the presence of 100–1000-fold excess of iron(III), copper(II), zinc(II), and nickel(II). Sorption capacity of TCC for all ions increases with the increase in the degree of substitution and changes in the series: AuIII > PdII > PtIV

\\\\Expert2\\nbo\\Russian Chemical Bulletin\\2010, 59 (7), 1303-1306.pdf
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