Porous powders useful as catalysts and catalyst matrices - comprising aggregates of aluminosilicate-coated oxide particles

摘要

New porous powder compsns. comprise porous aggregates of non-porous (to N2) spheroidal particles with a size of 3-90 nm. The particles consist of (a) a core of SiO2, aluminosilicate or Al2O3, ZrO2, TiO2, ThO2 and/or rare earth metal (RE) oxide; (b) a layer, =0.5nm thick, of an amorphous hydrated aluminosilicate having a Si:Al molar ratio of 1-19:1 and contg. one or more cations selected from H, NH4, Na, K, Cs, Li, Rb, Mg, Th, Ca, Sr, Ba, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, La, Ce, RE, Hf, Ta, W, Re, Os, Ir, Pt, Au, Sn, Cd, Bi and Sb; and opt. (c) an outer layer comprising 0-15 wt.% of a metal (or oxide) selected from Cs, Li, Rb, Mb, Ca, Sr, Ba, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Tc, Ru, Th, Rh, Pd, Ag, La, Ce, RE, Hf, Ta, W, Re, Os, Ir, Pt, Au, Sn, Cd, Bi and Sb. The compsns. have a specific surface of 30-750 m2/g, an apparent density of =0.5g/cm3, and a pore dia. range of 20-250 angstroms. The pore size distribution is such that =90% of the 20-45 angstroms pore vol. is in pores of dia. (0.6-1.4)D and =80% of the 45-250 angstroms pore vol. is in pores of dia. (0.6-1.4)D, where D is the av. pore dia. Also claimed are aluminosilicate aquasols with a Si:Al molar ratio of 1-19:1 comprising particles of dia. 3-90 nm, with a max. standard deviation of 0.37d, where d is the wt.-av. particle dia. The powder compsns. can be used as catalysts (e.g. for cracking, reforming, isomerisation, hydrocracking, synthesis of methylamines from MeOH and NH3) and as matrix materials for zeolite cracking catalysts. Their pore size can be controlled within a narrow range, giving high selectivity.