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Egiazarov, Yu. G.; Kravchuk, L. S.; Radkevich, V. Z.; Ivko, A. A.; Bogushevich, S. E.

doi:10.1023/a:1015552403741

Cited by 3 publications

(3 citation statements)

References 2 publications

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“…Although macroporous or swelled resins could allow the diffusion of large molecules and their approach to the reactive sites, the bead form of the resins may induce some kinetic limitations; therefore, fibers have been successfully experienced as another physical form for ion-exchange resins. Different types of such fibers in the form of nonwoven fabrics are known: (i) linear polystyrene fibers imbedded in a polypropylene matrix, , (ii) polypropylene fibers which were surface-grafted by polystyrene oligomers, ,, and (iii) polypropylene and cellulose fibers grafted with sulfopropyl or aminopropyl groups…”

Section: Discussionmentioning

confidence: 99%

Organic Synthesis by Catalysis with Ion-Exchange Resins

Gelbard

2005

Ind. Eng. Chem. Res.

178

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This review is intended to give a wide scope on the uses of ion-exchange resins as catalysts or catalyst precursors in organic synthesis, for the preparation of fine or intermediate chemicals. Twelve families of reaction have been covered and presented according to the molecules to be synthesized, regardless of the anionic or cationic nature of the resins; thus, ∼300 references have been selected from January 1980. In acid-catalyzed reactions, the contribution of both Lewis acidity and Bro ¨nsted acidity are mentioned, and, when available, some aspects related to the stability or the recycling of the catalysts are reported. In base-catalyzed reactions, the importance of the thermal stability of anionic resins has been underlined. A table that is included as an appendix provides some data on the resins quoted here.

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Section: Discussionmentioning

confidence: 99%

Organic Synthesis by Catalysis with Ion-Exchange Resins

Gelbard

2005

Ind. Eng. Chem. Res.

178

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“…The deviations from the theoretical values might be caused by further decomposition of the sulfonic group into sulfur trioxide during the thermolysis. 19,20…”

Section: Thermolysis Of the Copolymersmentioning

confidence: 99%

Sulfonated copolymers with SO₃H and COOH groups for the hydrolysis of polysaccharides

Jiang

et al. 2012

J. Mater. Chem.

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The well-defined sulfonated block copolymer poly(acrylic acid)-block-poly(styrene sulfonic acid) (PAA-b-PSSH) and the random copolymer poly(acrylic acid)-random-poly(styrene sulfonic acid) (PAA-r-PSSH) were prepared by direct thermolysis of the precursor copolymers poly(tert-butyl acrylate)-block-poly(neopentyl styrenesulfonate) (PtBA-b-PNSS) and poly(tert-butyl acrylate)random-poly(neopentyl styrenesulfonate) (PtBA-r-PNSS), which were synthesized by living radical polymerization (MWD < 1.10) catalyzed with CuBr. GPC, EA, 1 H NMR and FT-IR spectra were employed to characterize the structure of the synthesized acid polymers. The catalytic performance of the acid polymers was evaluated for the hydrolysis of starch and cellulose in aqueous solution under microwave irradiation. With the same effective acid concentration, the random copolymer PAA-r-PSSH gave the highest glucose yield among the prepared catalysts. It is believed that the good results were caused by the synergic effect of the SO 3 H and COOH groups in the polymer chain. In addition, microwave irradiation led to better glucose yields in the hydrolysis of polysaccharides than the conventional heating method with acid polymers as catalysts.

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“…In particular, a mass-spectrometric study (10 37 torr) of the physicochemical properties of FIBAN K-1 sulfonic cation exchanger in the alkali metal and alkaline-earth metal forms showed that the Mg form had the highest thermal stability [4,5]. Hence, the Mg form can be used as a support for metal catalysts of redox reactions.…”

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confidence: 99%

Thermal stability and activity in hydrogen oxidation of palladium catalysts supported on fibrous sulfonic cation exchanger in the hydrogen and magnesium forms

et al. 2004

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The effect of reduced palladium on the thermal stability of the hydrogen and magnesium forms of FIBAN K-1 fibrous sulfonic cation exchanger was studied. The activity of palladium catalyst supported by the H and Mg forms of the cation exchanger in hydrogen oxidation was determined, as influenced by the temperature of treatment of the catalyst with the reaction mixture.As shown previously [135], the thermal stability of sulfonic cation exchangers in the metal forms is higher than that of the H forms. In particular, a mass-spectrometric study (10 37 torr) of the physicochemical properties of FIBAN K-1 sulfonic cation exchanger in the alkali metal and alkaline-earth metal forms showed that the Mg form had the highest thermal stability [4,5]. Hence, the Mg form can be used as a support for metal catalysts of redox reactions.However, the effects exerted by the metal phase on the thermal stability of sulfonic cation exchanger and by the metal cation on the catalytic activity of the supported metal were not understood. In this work we studied the thermal stability of the H and Mg forms of FIBAN K-1 sulfonic cation exchanger containing reduced palladium, the palladium dispersity in these matrices as influenced by the exchangable cation, and the palladium activity in hydrogen reduction as influenced by the temperature of the treatment of the catalysts with the reaction mixture. EXPERIMENTALThe H form of FIBAN K-1 fibrous sulfonic cation exchanger was prepared by bulk radiation grafting of styrene (98%)3divinylbenzene (2%) copolymer to polypropylene staple fiber, followed by sulfonation of the poly(styrene3divinylbenzene) matrix with concentrated H 2 SO 4 [6].Pure Mg form was prepared by washing of a column packed with the H form (exchange capacity 3 mg-equiv g 31 ) with excess 0.5 M MgCl 2 solution until pH of the solution at the outlet became neutral. Then the column was washed with distilled water until the absence of chloride ions in the wash waters and then was dried in air.To prepare catalysts with 2.5 wt % Pd content, the H or Mg form of the cation exchanger was treated under static conditions with a solution of tetramminepalladium(II) chloride [Pd(NH 3 ) 4 )]Cl 2 of a definite concentration at room temperature and pH 838.5. The Pd(II) concentration in the solutions before and after ion exchange was measured spectrophotometrically [7]. Then the samples were washed with distilled water until the absence of chloride anions in the wash waters, and the [Pd(NH 3 ) 4 ] 2+ cations were reduced with an aqueous solution of N 2 H 4 . H 2 O at 40oC for 30 min. After that, the samples were washed again with distilled water to neutral reaction and were dried at room temperature.To determine the degree of Pd(II) reduction, the ion-exchangeable Pd(II) species were completely washed out from the samples with excess 1 M NaCl and then the palladium concentration in the solution was measured. In the course of reduction, the ionexchange sites of the catalyst are converted to the H form after removal of [Pd(NH 3 ) 4 ] 2+ cations. To conv...

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Cited by 3 publications

References 2 publications

Organic Synthesis by Catalysis with Ion-Exchange Resins

Organic Synthesis by Catalysis with Ion-Exchange Resins

Sulfonated copolymers with SO₃H and COOH groups for the hydrolysis of polysaccharides

Thermal stability and activity in hydrogen oxidation of palladium catalysts supported on fibrous sulfonic cation exchanger in the hydrogen and magnesium forms

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Untitled

Cited by 3 publications

References 2 publications

Organic Synthesis by Catalysis with Ion-Exchange Resins

Organic Synthesis by Catalysis with Ion-Exchange Resins

Sulfonated copolymers with SO3H and COOH groups for the hydrolysis of polysaccharides

Thermal stability and activity in hydrogen oxidation of palladium catalysts supported on fibrous sulfonic cation exchanger in the hydrogen and magnesium forms

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Sulfonated copolymers with SO₃H and COOH groups for the hydrolysis of polysaccharides