Highly attrition resistant mesoporous catalytic cracking catalysts

• Main Author: WACHTER; WILLIAM A
• Format: Patent
• Language: English
• Published: 22.06.1993
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; CRACKING HYDROCARBON OILS; FUELS; LUBRICANTS; METALLURGY; MINERAL WAXES; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; TECHNICAL GASES CONTAINING CARBON MONOXIDE; THEIR RELEVANT APPARATUS; TRANSPORTING

A catalytic cracking catalyst for converting a hydrocarbon feedstock at elevated temperature in the substantial absence of hydrogen, into lower average molecular weight, lower boiling hydrocarbons useful as transportation fuels. The catalyst is a composite of a crystalline aluminosilicate zeolite in concentration ranging as high as about 80 percent, based on the total weight of the catalyst, within a mesoporous silica-alumina matrix. The matrix, preferably, is constituted of silica sols modified by alumina and clay and it is characterized as of polymodal pore size distribution, as measured by mercury porosimetry, a first mode wherein at least 75 percent, preferably about 80 percent to 90 percent, of the pore volume measured between 45 Angstroms and 2000 Angstroms is in pores greater than 160 Angstroms in diameter, and a second mode wherein up to about 20 percent of the pore diameters are greater than 100 Angstroms but less than 160 Angstroms in diameter. These catalysts are highly active, and selective in the production of olefins without high coke made. The attrition-resistance of these catalysts, as measured by the Davison Index, is quite low, ranging generally from about 1 to about 8, more generally from about 1 to about 5, or less.