Abstract: Porous silica-alumina particles in which pores with relatively large diameters are present at a high ratio with respect to the total pore volume, and the particles contain crystalline boehmite alumina, are disclosed. The crystalline boehmite alumina-containing porous silica-alumina particles are such that a specific surface area SA measured by the BET method is in a range of 400 to 600 m2/g, a pore volume PV measured by the BJH method is in a range of 1.0 to 2.2 ml/g, a ratio P10 of a pore volume of pores having pore diameters PD of 10 nm or larger to the total pore volume PV is in a range of 60% or higher, the pore volume of pores having pore diameters of 10 nm or larger being measured by the BJH method, and a mass ratio S/A between silica and alumina is in a range of 2/98 to 70/30.

Abstract: A silica-alumina powder, a method for producing the same, and a fluid catalytic cracking catalyst including this silica-alumina powder are provided. The silica-alumina powder contains SiO2 within a predetermined range, has a specific surface area within a predetermined range, and has a pore volume and an acid amount within predetermined ranges. An alumina raw material includes one of boehmite, pseudo-boehmite, and mainly amorphous alumina gel. The method for producing the silica-alumina powder includes a step of mixing an aqueous solution including alumina hydrate and an aqueous solution containing a silica precursor to prepare an aqueous solution including a silica-alumina precursor; a step of adjusting the pH of the aqueous solution to be within a predetermined range, and then heat-treating the aqueous solution; and a step of cooling the aqueous solution or silica-alumina slurry, then separating and washing a solid, and then drying or further calcining the solid.

Abstract: An aluminum phosphate-modified metal-supported crystalline silicoaluminophosphate NOx-reducing catalyst includes metal-supported crystalline silicoaluminophosphate particles having a surface modified with aluminum phosphate.