Article ID Journal Published Year Pages File Type
41884 Applied Catalysis A: General 2010 9 Pages PDF
Abstract

ZrO2/SiO2 mixed oxides with different ratios (2:1 to 4:1) were prepared by a deposition–precipitation method from zirconium hydroxide and colloidal silica and used as supports for platinum nano-particles. The synthesized catalysts along with Pt/ZrO2 reference materials were tested for CH4 reforming with CO2 at a high temperature of 1073 K and at high space velocity.Very high reforming activity was observed for the Pt/ZrO2/SiO2 (4:1) sample among all the prepared catalysts. The effect of zirconia to silica ratio on the physico-chemical properties that determine the catalytic activity has been investigated characterizing all the catalysts after calcination, reduction as well as after reaction with several techniques. From X-ray diffraction patterns, BET and H2 chemisorption measurements, X-ray photoelectron and FTIR spectra, the better catalytic properties of the Pt/ZrO2/SiO2 (4:1) sample have been explained by higher Pt dispersion due to the absence of remaining free silica and the presence of amorphous ZrSiO4 in higher amount. Additionally, a better thermal stability of the prepared ZrO2/SiO2 supports compared to ZrO2 was evidenced after ageing at 1073 K for 16 h in particular for the ratio 4:1. It also underlines the interest of the preparation method.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image ( K)Download as PowerPoint slideResearch highlights▶ High dry reforming activity was obtained with Pt supported over ZrO2/SiO2 supports. ▶ The best support contained no remaining free silica but ZrSiO4 in higher amount. ▶ The higher activity of the best catalyst was due to higher Pt dispersion. ▶ Improved thermal stability of the ZrO2/SiO2 supports compared to ZrO2 was evidenced.

Related Topics
Physical Sciences and Engineering Chemical Engineering Catalysis
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