FCC CATALYST WITH ENHANCED MESOPOROSITY, ITS PREPARATION AND USE
Process for the preparation of a catalyst by adding, clay, boehmite, a first silica to form a slurry, digesting the slurry with a monoprotic acid to a pH of less than 4, adding one or more zeolites, adding a rare earth component to the slurry and mixing, adjusting the slurry pH to below 4 with monoprotic acid, adding a second silica anywhere in the preceding steps, destabilizing the slurry by raising the pH, shaping and collecting the resulting catalyst, wherein the resulting catalyst has enhanced mesoporosity.
1 . A process for the manufacturing of a catalyst composition comprising the steps of:
a. Adding, clay, boehmite, a first silica to form a slurry;
b. Digesting the slurry with a monoprotic acid to a pH of less than 4;
c. Adding one or more zeolites from the group of ultra stabilized high SiO2/Al2O3 Y zeolite, rare earth exchanged USY, rare earth exchanged Y zeolites, zeolites with pentasil and beta structures to the slurry and mixtures thereof;
d. Adding a rare earth component to the slurry either after step (a) or after step (c) and mixing;
e. Adjust the slurry pH to below 4 with monoprotic acid;
f. Adding a second silica anywhere in the above steps a-e;
g. Destabilizing the slurry by raising the pH to above 4.0;
h. Shaping and collecting the resulting catalyst.
i. Optionally followed by a calcination and post washing step to remove excess sodium as necessary.
2 . The process of claim 1 wherein the first silica comprises sodium stabilized colloidal silica.
3 . The process of claim 1 wherein the second silica comprises acidic colloidal silica or ammonia stabilized colloidal silica or low-sodium stabilized colloidal silica or polysilicic acid, or mixtures thereof.
4 . The process of claim 1 wherein the one or more rare earth components are added to the catalyst as hydroxide, chloride, oxide, nitrate, sulfate, oxychlorides, acetates, or carbonates.
5 . The process of claim 4 wherein the one or more rare earth components comprise lanthanum nitrate.
6 . The process of claim 1 wherein the resulting catalyst has increased mesopores in the range of 6-40 nm compared to standard base catalysts.
7 . The process of claim 1 wherein the resulting catalyst further comprises a pore diameter distribution having a peak at a pore diameter of about 2.0 to about 6 nm.
8 . The process of claim 1 wherein the resulting catalyst further comprises about 20 to about 30% of total pore volume contributed by pores having a diameter of about 2.0 to about 6 nm and 55 to about 70% of total pore volume by pores having a diameter of about 6 to 40 nm.