Stability and Performance of Ruthenium Catalysts Based on Refractory Oxide Supports in Supercritical Water Conditions

作者：Zoehrer Hemma; Mayr Franziska; Vogel Frederic^*

来源：Energy & Fuels, 2013, 27(8): 4739-4747.

DOI：10.1021/ef400707f

Eleven commercial stabilized and unstabilized zirconia and titania samples have been tested for stability as potential catalyst supports for supercritical water gasification at 400 degrees C and 28.5 MPa. Samples based on monoclinic zirconia and rutile as well as one sample based on stabilized tetragonal zirconia showed good physical stability. Most samples showed a loss of surface area during the first 20 h of hydrothermal treatment, leveling out at longer exposure times. In a continuous fixed-bed reactor setup, a performance and stability test of the samples loaded with 2 wt % ruthenium gave good results for three samples, of which the sample based on stabilized tetragonal zirconia showed the best performance. For those samples, the surface area decreased only to a minor extent, which we attribute to an aging step that has been performed prior to impregnation with ruthenium. The metal surface area showed a minor decrease for all samples. The reason for this decrease is probably the build-up of a layer of carbon deposit on top of the active sites.

• 出版日期2013-8