Wednesday, 2 November 2005 - 8:45 AM
307c

Nanogold Particle-Oxide Interaction for the Water Gas Shift Reaction

Danny Pierre1, Maria Flytzani-Stephanopoulos1, Mark E. Bussell2, Weiling Deng1, and Gajanthan Balakaneshan1. (1) Chemical and Biological Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, (2) Chemistry Department, Western Washington University, 516 High Street, MS-9150, Bellingham, WA 98225-9150

The importance of nanogold–oxide interaction for CO oxidation reactions has been discussed extensively in the literature.  For the water-gas shift (WGS) reaction, our group has shown that there is a strong interaction between gold and cerium oxide.  The presence of gold ions on the defect sites of ceria is a key feature of Au-ceria catalysts [1-3].  The importance of metallic gold nanoparticles has also been argued in the literature [4].  Conventional techniques such as co-precipitation, deposition-precipitation, and cogelation are typically used to prepare these catalysts.   

Recently the use of reverse micellar systems has been reexamined due to their ability to make highly structured uniform catalysts [5].  The technique has already been used to make both encapsulated Pt and Pd catalysts for butane combustion [6].  In this work, we look at several nano gold-oxide materials; namely Au/SiO2, Au/CeO2-doped SiO2, and Au/Fe2O3 for the WGS reaction.  Materials included encapsulated gold within a shell of oxide (via the reverse micelle technique) and traditionally structured catalysts.  The catalysts were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), BET surface area and H2S temperature-programmed desorption (TPD) measurements, as well as by H2 and CO temperature-programmed reduction (TPR). Catalyst activities were evaluated for the WGS reaction under various conditions that included product-free and full reformate gas mixtures, as well as in the presence and absence of ppm levels of H2S to investigate the effects of poisons.  

References:

1.               Q. Fu, H. Saltsburg, and M. Flytzani-Stephanopoulos, Science 301 (2003) 935-938

2.               Q. Fu, W. Deng, H. Saltsburg, and M. Flytzani-Stephanopoulos, Applied Catalysis B 56 (2005) 57-68.

3.               ZP Liu, SJ Jenkins, and DA King,  Physical Review Letters 94 (2005)

4.               H. Sakuraia, T. Akitaa, S. Tsubota, M. Kiuchia and M. Haruta,  Applied Catalysis A (2005), in press

5.               S. Eriksson, U. Nylén, S. Rojas and M. Boutonnet,  Applied Catalysis A 265 (2004) 207-219.

6.               K. Yu, C. Yeung, D. Thompsett, and S. Tsang, J. Phys. Chem. B 107 (2003) 4515-4526  

 


See more of #307 - Catalytic Hydrogen Generation for Fuel Cell Applications I (20006)
See more of Catalysis and Reaction Engineering Division

See more of The 2005 Annual Meeting (Cincinnati, OH)