Influence of Cerium Additive on the Reduction Behaviour of Tungsten Oxide under Carbon Monoxide Atmosphere

Abstract:

The reduction of pure WO₃ and Ce/WO₃ has been studied by using temperature programmed reduction (TPR), X-ray diffraction (XRD), and FESEM analysis. The reduction behavior were examined by non-isothermal reduction up to 900 oC then continued with isothermal reduction at 900 oC for 45 min under (40% v/v) carbon monoxide in nitrogen (CO in N₂) atmosphere. The TPR results shows that reduction peak of Ce/WO₃ were shifts to lower temperature as compared with to the pure WO₃. In addition, TPR results indicate that addition with ceria give better reducibility compared to pure WO₃. Based on the characterization of the reduction products after hold 45 min using XRD, pure WO₃ were completely converted to WO₂ and W metal phases. While, after addition of Ce to the WO₃, the reduction was enhanced to W phases and some suboxide W₅O₁₄ and W₃O₅ with no WO₂ phase remained and carbide observed. This is associated to the formation of alloy complex Ce₂WO₆ which gave remarkable effect to the reduction.

• Periodical: Materials Science Forum (Volume 888)
• Pages: 389-393
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.888.389
• Online since: March 2017
• Authors: Fairous Salleh*, Tengku Shafazila Tengku Saharuddin, Alinda Samsuri, Rizafizah Othaman, Mohammad Wahab Mohammad Hisham, Mohd Ambar Yarmo
• Keywords: Carbon Monoxide, Ceria, TPR, Tungsten, Tungsten Oxide, X-Ray Diffraction (XRD)

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