Thermal stability and characterization of γ-Al2O3 modified with rare earths

Rare earth metals for automotive exhaust catalysts

“…Transitional alumina as catalyst support is transformed into ␣-alumina, which decreases its high surface area significantly under high temperature operation. This leads to agglomeration of noble metal on the catalyst support, and thus a decrease of catalytic activity [13,14].…”

Thermal stabilization of γ-alumina with modification of lanthanum through homogeneous precipitation

“…Since the temperature in the catalyst can rise to over 1000 • C in a recent engine, the thermal stabilization of catalysts is important. The additive of lanthanum species greatly improves the thermal stability to inhibit the sintering and phase transformations of alumina [3][4][5][6][7]. The methods of adding La to alumina are important to the practical fabrication of catalysts.…”

Suppression of Noble Metal Sintering Based on the Support Anchoring Effect and its Application in Automotive Three-Way Catalysis

“…It has been trying many methods to improve catalytic activity after ageing the catalysts; improving noble metal dispersion with high surface area supports, adding some promoters, and improving thermal stability of these supports and promoters, etc. [1][2][3][4][5][6][7]. However, it has not been established a valid method for suppressing noble metals sintering and it eventually has resulted to use lots of noble metal for catalysts to meet the stringent emission restrictions.…”