Chemical Catalysis

Zirconia can be used in a wide range of catalysis applications outside of the traditional automotive applications.

for example there are many environmental catalysis applications for pollution control of stationary sources, refining applications such as hydrogenation, oxidation, amination, isomerisation and other catalytic reactions where Strong acid catalysts based on sulfated and tungstated zirconia are excellent Friedel Krafts and isomerisation catalysts.

 

ENVIRONMENTAL CATALYSTS

Zirconium based catalysts can be used in pollution control in mobile and stationary sources. MEL Chemicals can supply an extensive range of zirconia and doped zirconia powders and precursors (aqueous zirconium salts and organic soluble complexes).

 

REFINING & CHEMICAL CATALYSTS

Zirconium based catalysts can be used in hydrogenation, oxidation, amination, isomerisation and other catalytic reactions. Strong acid catalysts based on sulfated and tungstated zirconia are excellent Friedel Krafts and isomerisation catalysts.

 

REFORMING CATALYSTS FOR FUEL CELLS

MEL Chemicals supply a range of high purity, fully or partially stabilised yttria zirconia powders, for use as electrolytes and anodes in SOFC systems. The range contains sinter-active, sub-micron powders which, when fired, produce dense, non-porous layers. A range of ceria-stabilised zirconia powders for fuel processing catalysts is also available. These have controlled particle size, redox properties and surface chemistry, which can be fine-tuned for use in reforming.

 

POWDER CHARACTERISTICS

Zirconium oxides / hydroxides in their undoped and doped forms, can modify the nature of catalyst supports in respect of surface area stability, porosity, surface acidity / basicity and crystallinity.

We supply initial samples in the form of dry hydroxide precursors so that addition of other reagents and calcination / activation procedures can be optimised in-house.

Calcination converts amorphous, microporous hydroxides to crystalline, mesoporous oxides. Activation guidelines are available on request. Dopants stabilise the tetragonal / cubic zirconia phases, usually favoured over the more stable monoclinic phase. Doped zirconias generally show improved stability of surface area up to ~1200°C and exhibit single phases (tetragonal or cubic) up to ~1000°C. We have developed proprietary technology for enhancing the stability of surface area, porosity and phase composition at high temperatures.

The product of choice will depend upon the catalytic properties required (acid, base etc.) as well as the form that the catalyst will be in (slurry, washcoat, extrudate, tablet, etc.). We also have the technology to fine-tune and control the particle size to suit the specific application.

 

 FORMED PRODUCTS

Formed products, based on our powders, are not produced in house but we have contacts with several companies who have experience forming our products. Please contact us for further information.