Catalytic properties of chromium–palladium loaded alumina in the combustion of methane in the presence of hydrogen sulfide

A comparative study of the water-gas shift activity of Pt catalysts supported on single (MOx) and composite (MOx/Al2O3, MOx/TiO2) metal oxide carriers

“…3 and 4 and Table 2 show that addition of MO x results in all cases in enhanced WGS activities, compared to that obtained for Pt/ Al 2 O 3 . Similar effects have been frequently observed for a number of catalytic reactions [21][22][23][24][25][26][27][28][29][30][31][32] including oxidation of CO or CH 4 [21,22], reduction of NO by propene [23], reduction of N 2 O by hydrogen or CO [24] and CO 2 reforming of CH 4 [25]. The improved catalytic performance induced by the presence of MO x has been attributed to several factors, including increased reducibility of the support [25,27,28], stabilization of noble metal crystallites against sintering [21,24] and/or creation of new active sites at the metal-support interface [21,25,26,29,37].…”

“…Metal oxides (MO x ) with small primary particles size may be produced by dispersion of MO x on high surface area supports, such as Al 2 O 3 or SiO 2 , which has been reported to result in significant enhancement of activity, selectivity and/or stability of dispersed noble metals for a number of catalytic reactions [21][22][23][24][25][26][27][28][29][30][31][32]. In the present study, the water-gas shift activity of platinum catalysts dispersed on composite MO x / Al 2 O 3 or MO x /TiO 2 supports is investigated and results are compared to those obtained for Pt catalysts supported on the corresponding single metal oxides.…”

The Effect of Chromium on Sulfur Resistance of Pd/HY–Al2O3 Catalysts for Aromatic Hydrogenation

“…Primet et al (43) studied the catalytic properties of CrPd/alumina in the combustion of methane in the presence of H 2 S. In the case of the fresh catalyst, palladium participates in a strong interaction with the chromium-containing phase (Cr 3+ or Cr 2 O 3 ), and electron density of palladium can be withdrawn by such species (43). In contrast, theoretical calculation shows that the alloying of Pd with Cr (such as Pd 3 Cr and PdCr) results in an electron transfer from Cr to Pd because Cr is more electropositive (44).…”

Destruction of Volatile Organic Compounds by Catalytic Oxidation

“…Ferrandon have made a short review of these interactions (Ferrandon, 2001). Some examples of synergism are: doping Pd with oxides of Co or Cr it is restrained the poisoning effect of sulphur (Khairulin et al, 1997); by incorporation of Pt and Pd into metal oxides the selectivity toward CO 2 is increased (Ménézo et al, 1993); the activity of Pd on CH 4 oxidation is increased by addition of metal oxides, particularly oxides of Ni (Widjaja et al, 1999).…”