Effects of Cl on the reduction of supported PdO in ethanol/water solvent mixtures. (3rd April 2017)

• Record Type: Journal Article
• Authors: Brazier, John B.; Newton, Mark A.; Barreiro, Elena M.; Parry, Stephen; Adrio, Luis A.; Mulligan, Christopher J.; Hellgardt, Klaus; Hii, King Kuok (Mimi); Thompson, Paul B. J.; Nichols, Rachel; Nguyen, Bao N.
• Is Part Of: Catalysis, structure & reactivity. Volume 3:Number 1/2(2017)
• Page Start: 54
• Page End: 62
• Publication Date: 2017-04-03
• Subjects: Quick EXAFS -- chlorine -- Palladium -- green solvents -- reduction -- hydride formation -- operando measurement; Catalysts -- Periodicals; Catalysis -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; 660.2995
• DOI: 10.1080/2055074X.2016.1267296
• Languages: English
• ISSNs: 2055-074X

Abstract

Abstract: The reduction of γ-Al2 O3 -supported PdO in flowing aqueous ethanol was investigated. Quick EXAFS (QEXAFS) performed at the Pd K-edge reveals that the presence of Cl can have a profound effect on the reduction process. At low loadings of Pd (1 wt-%), the size dependency of the process is inverted, compared to Cl-free samples. The extent of reduction was found to be dependent on loading/particles size. It is shown, using in situ QEXAFS at the Cl K- and Pd L3 -edges, that residual Cl is not removed by the flowing solvent mixture, even at an elevated temperature of 350 K. The origins of these behaviours are discussed in terms of the differing effects that Cl may have when bonded to oxidic or reduced metal centres and the results were compared to earlier observations made on the effects of Cl on commercial polyurea encapsulated Pd ENCAT™ NP 30 catalysts. Abstract :