Optimal Pt load of a Pt/La2O3·SiO2 highly selective WGS catalyst usedin a Pd-membrane reactor

CAROLINA CORNAGLIA , JOHN MÚNERA, EDUARDO LOMBARDO; SILVANO TOSTI

APPLIED CATALYSIS A-GENERAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 486 p. 85 - 93

0926-860X

tPt(wt%)/La2O3(27)·SiO2catalysts with wt% = 0.02 up to 1.2 were synthesized and tested in a conventionalfixed-bed reactor. In differential mode, the Pt(0.1)/La2O3(27)·SiO2catalyst showed higher activity pergram of Pt than the other solids. XPS showed the presence of only surface metallic platinum, in boththe fresh and used Pt(0.1 wt%) formulation, which could be responsible for the high catalytic activity.At higher Pt loads both Pt+ and Pt◦species were present at the surface. The presence of La2Si2O7in allsolids was detected by XRD. Graphitic carbon in the used catalysts was not detected through laser Ramanspectroscopy.Different catalytic tests were carried out in a tubular Pd-membrane reactor feeding a reformer outlettype stream with a molar composition of 40% H2, 40% H2O, 12% CO2and 8% CO. They were performedbetween 673 and 723 K and at pressures ranging from 100 kPa to 800 kPa. At 723 K and 800 kPa, theCO conversion and H2recovery values were 96% and 88%, respectively. A stability test including severalstart-up and shut-down cycles showed high stability of the Pt(0.1) catalyst.