Metal palladium dispersed inside macroporous ion-exchange resins: the issue of the accessibility to gaseous reactants

• Published in: Journal of molecular catalysis. A, Chemical Vol. 151; no. 1; pp. 283 - 288
• Main Authors: Biffis, A, Landes, H, Jeřábek, K, Corain, B
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.02.2000; Elsevier
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Exact sciences and technology; General and physical chemistry; Ion exchangers; ISEC; Palladium; Polymer supports; Pulse chemisorption; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Pulse chemisorption; Palladium; ISEC; Polymer supports; Ion exchangers; Chemisorption; Transmission electron microscopy; Gas solid interface; Polymer; Transition metal; Platinoid; Porous material; Ion exchange resin; Supported catalyst; Macroporosity
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/S1381-1169(99)00268-X

Commercial macroporous ion-exchange resins (Lewatit SPC 118 and UCP 118) were used to support Pd metal by a two step ion-exchange and reduction procedure. The textural features of the resins were determined by Inverse Steric Exclusion Chromatography (ISEC) measurements. TEM characterization of the obtained Pd/resin composite showed the presence of uniformly sized Pd crystallites located at the macropore “surface”. Pulse chemisorption analysis gave evidence for the lack of accessibility of the crystallites when the resin composite is in the dry state. This suggests that the metal particles are in fact embedded in a gel-type resin layer at the “surface” of the macropores and therefore practically unaccessible to the molecules of a gaseous phase unless the support is in the swollen state.