Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
MODELING OF THE DEACTIVATION OF POLYMER-SUPPORTED PALLADIUM CATALYSTSIN THE HYDROGENATION OF 4-NITROTOLUENE
Autore:
KRALIK M; FISERA R; ZECCA M; DARCHIVIO AA; GALANTINI L; JERABEK K; CORAIN B;
Indirizzi:
SLOVAK TECH UNIV,DEPT ORGAN TECHNOL,RADLINSKEHO 9 BRATISLAVA 81237 SLOVAKIA UNIV PADUA,DIPARTIMENTO CHIM INORGAN METALLORGAN & ANALI I-35131 PADUA ITALY UNIV AQUILA,DIPARTIMENTO CHIM INGN CHIM & MAT I-67010 COPPITO ITALY ACAD SCI CZECH REPUBL,INST CHEM PROC FUNDAMENTALS CR-16502 PRAGUE 6 CZECH REPUBLIC
Titolo Testata:
Collection of Czechoslovak Chemical Communications
fascicolo: 7, volume: 63, anno: 1998,
pagine: 1074 - 1088
SICI:
0010-0765(1998)63:7<1074:MOTDOP>2.0.ZU;2-G
Fonte:
ISI
Lingua:
ENG
Soggetto:
PHYSICOCHEMICAL PROPERTIES; REACTION-KINETICS; 2,4-DINITROTOLUENE; RESINS;
Keywords:
HYDROGENATION; 4-NITROTOLUENE; ION-EXCHANGE POLYMERS; POLYMER-SUPPORTED PALLADIUM CATALYSTS; CATALYST DEACTIVATION; HETEROGENEOUS CATALYSIS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
28
Recensione:
Indirizzi per estratti:
Citazione:
M. Kralik et al., "MODELING OF THE DEACTIVATION OF POLYMER-SUPPORTED PALLADIUM CATALYSTSIN THE HYDROGENATION OF 4-NITROTOLUENE", Collection of Czechoslovak Chemical Communications, 63(7), 1998, pp. 1074-1088

Abstract

The kinetics of the hydrogenation of 4-nitrotoluene over Pd catalystssupported on sulfonated polystyrene and simultaneous deactivation of these catalysts were investigated. Reaction rates of both the hydrogenation and the dissolution of Pd crystallites were related to the totalPd surface. The average radius of ideal spherical crystallites, as determined by X-ray powder diffraction analysis, was taken as the starting value of the crystallite size. Stability of the polymer network waschecked by Inverse Steric Exclusion Chromatography (ISEC). The ESR and Static Gradient field Spin Echo (SGSE) NMR spectroscopies were used to assess the accessibility and diffusivity before and after deactivation experiments. Langmuir-Hinshelwood type kinetic models were appliedto describe the hydrogenation of 4-nitrotoluene. The kinetic law was incorporated into a more comprehensive model involving also diffusion of reactants inside catalytic particles. Simultaneous treatment of a few sets of kinetic data from batch hydrogenation carried our at 0.25-0.75 MPa yielded reliable values of model parameters. The model showed an increasing rate of dissolution of palladium with decreasing concentration of hydrogen and increasing concentration of 4-nitrotoluene. Thelatter fact supports the hypothesis that the nitro compound is the oxidant responsible for the dissolution of palladium.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 24/09/20 alle ore 03:47:50