Catalyst compositions comprising small size molecular sieves crystals deposited on a porous material

A process of preparation of a catalyst composition comprising:

• a) providing an inorganic porous material;
• b) optionally calcinating the inorganic porous material at temperature from 400° C. to 1200° C.;
• c) providing a solution containing at least one charge surface modifying agent selected from the group consisting of inorganic surface modifying agents, ionic or non-ionic surfactants, water soluble anionic polymers, and water soluble cationic polymers;
• d) putting in contact the solution of step c) and the inorganic porous material to obtain a modified inorganic porous material modified with a charge surface modifying agent;
• e) providing a solution containing precursors for a molecular sieve;
• f) preparing the molecular sieves by:
• i) maturating, during a period of time from of no more than 100 h, the solution of step e), the maturating process being followed by dynamic light scattering (DLS) and stopped when crystals of molecular sieve have a maximum size of 50 nm, and subjecting the modified inorganic porous material to a contact with the maturated solution to deposit molecular sieve crystals on the surface of the modified inorganic porous material obtained at step d);
• and/or
• ii) putting in contact the modified inorganic porous material obtained at step d) with the solution of step e) and maturating during a period of time of no more than 100 h the obtained mixture until the acidity of the catalyst composition measured by TPD ammonia has increased by at least 10% compared with the acidity of the inorganic porous material;
• g) separating solid from liquid if any of the mixture obtained after step f);
• and
• h) calcinating the solid obtained at step g) to form the catalyst composition, wherein the catalyst composition comprises:
• an inorganic porous material with pore diameters of at least 2 nm and crystals of molecular sieve;
• wherein the crystals of molecular sieve have an average diameter not bigger than 50 nm measured using Scanning Electron Microscopy, wherein the crystals of molecular sieve comprise a zeolite selected from the group consisting of MOR, FAU, EMM, MWW, BETA, ZSM-21, ZSM-42, AEI, CHA, ERI, LEV, OFF, ZSM-34, AFI, AEL, LTL, MFI (ZSM-5, silicalite, TS-1), MEL (ZSM-11, silicalite-2, TS-2), MTT (ZSM-23, EU-13, ISI-4, KZ-1), MFS (ZSM-57), HEU (Clinoptilolite), FER (ZSM-35, Ferrierite, FU-9, ISI-6, NU-23, Sr-D), TON (ZSM-22, Theta-1, ISI-1, KZ-2 and NU-10), LTL (L), MAZ (mazzite, Omega, ZSM-4) and mixtures thereof;
• wherein the catalyst composition has a concentration of acid sites ranging from 50 to 1200 μmol/g measured by Temperature-Programmed Desorption of ammonia, TPD NH3;
• and
• wherein an X-ray diffraction pattern of the catalyst composition is the same as an X-ray diffraction pattern of the inorganic porous material.