Preparation of Apatite-type Lanthanum Silicate Supported Catalysts for Pollutant Gas Purification

Noble metal loaded apatite-type lanthanum silicate and γ-alumina catalysts were prepared. Single phase La 9.33 Sι 6 O 26 , was obtained by sol-gel method using lanthanum oxide and tetraethyl orthosilicate (TEOS). Pd/Lag 33 Si 6 O 26 catalyst exhibited high activity for oxidation of C 3 H 6 comparable to Pd/Al 2 O 3 catalysis with higher surface area than Laq 33 Si 6 O 26 . Pt/La 9.33 Si 6 O 26 catalyst exhibited higher catalytic activity for removal ofNOx than that of Pt/Al 2 O 3 catalyst. These results suggested that noble metal loaded apatite-type silicates were candidate catalysts for exhaust gas purification.