反应详情

Yttrium nitrate hexahydrate 3.82 g and lanthanum nitrate hexahydrate 0.997 g were dissolved in 11.5 g of water to provide an aqueous solution of yttrium nitrate-lanthanum nitrate mixture. Fifteen (15.0) g of silica gel (CARIACT-30® manufactured by Fuji Devison) was impregnated with the solution prepared as described above and dried at 120° C. in air, followed by a sequential calcination in air at 500° C. for 5 hours and in nitrogen at 500° C. for 5 hours. Thus, yttrium and lanthanum oxides as supported on the silica gel were obtain. This product was labelled Catalyst (7). This support type catalyst contained 7.5 wt % of yttrium oxide and 2.5 wt % of lanthanum oxide, and had a specific surface area of 110 m2 /g.