Synthetic catalysts and molecular sieves of zeolite compsn - with amorphous structure and increased pore size

摘要

Amorphous porous inorganic gels made from mixts. contg. SiO2, Al2O3, Na2O, K2O and water in molar ratios of SiO2/Al2O3 8-30:1, (K2O+Na2O)/SiO2 0.3-0.8:1, Na2O/K2O 0.001-1.5:1 and H2O/(K2/+Na2O) 20-45:1 by heat-ageing the suspension, isolating the prod. and opt. carrying out an ion exchange with ammonium hydrogen and/or metal ions of Groups II to VIII. Heat ageing is for 3-12 h. at 50-120 degrees C. Used as catalysts for cracking, hydrocracking, hydrogenation, alkylation and reforming of hydrocarbons. Also are absorbents and molecular sieves for sepn. of large molecules. Pore sizes show a broad spread within the range 14-40 Angstroms in contrast to zeolites of faujasite type with pores around 14 Angstroms, making the pores more accessible to large hydrocarbon molecules. Surface area is high, in the range 300-900 m2/g. More easily and consistently made in large quantities than cryst. zeolites.