The method of preparation, ion exchange (IE) versus impregnation (IP), effects the final dispersion, acidity and sintering stability of L-zeolite supported catalysts. The origin of the dispersion effect appears to be in the shape and size of the PdO precursor formed upon calcination which is more elongated with respect to the zeolite channel and has a lower nearest neighbor oxide coordination number when IP is used. While acidity introduced into the L-zeolite before preparation does not appear to effect the initial dispersion, acidity introduced after reduction of the IE preparation stabilizes the Pd particles toward sintering in H2.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry