Modified zeolites and methods of making thereof

A method of forming modified zeolite particles comprising the steps of:

• synthesizing zeolite particles, said zeolite particles being crystalline,
• modifying the zeolite particles by shock annealing to reduce the water content while retaining reactivity toward acid species, wherein said shock annealing comprises:
• a) heating the zeolite particles to a temperature above a phase transformation temperature of the zeolite particles causing a phase transformation at a crystalline outer shell of said zeolite particles and thereby producing said modified zeolite particles;
• b) cooling said modified zeolite particles below the phase transformation temperature to limit the phase transformation to the outer shell of the modified zeolite particles.

A process of forming small size modified aluminosilicate zeolites having a narrow particle size distribution and a modified outer shell comprising:

• preparing a solution of sodium silicate;
• preparing a solution of sodium aluminate;
• preparing a solution of sodium hydroxide;
• adding the sodium hydroxide solution to the sodium aluminate solution;
• adding the sodium hydroxide/sodium aluminate solution to the sodium silicate solution allowing the resulting mixture to age for 0.1 to 48 hours prior to crystallization;
• crystallizing zeoliie particles in said mixture;
• washing and drying said zeolite particles;
• shock annealing said zeolite particles by heating the crystallized zeolite particles to a temperature above a phase transformation temperature of the zeolite particles causing the crystalline outer shell to be modified thereby forming said modified zeolite particles;
• and
• cooling said modified zeolite particles below the phase transformation temperature to limit the phase transformation to the outer shell of the modified zeolite particles.

A method of forming modified zeolite particles comprising the steps of:

• synthesizing the zeolite particles, the zeolite particles having a crystalline structure,
• dehydrating the zeolite particles,
• modifying the zeolite particles by shock annealing to reduce the water content while retaining reactivity toward acid species, said shock annealing comprising the steps of:
• a) heating the zeolite particles to a temperature above a phase transformation temperature of the zeolite particles causing a phase transformation at a crystalline outer shell thereby producing said modified zeolite particles, and
• b) cooling said modified zeolite particle below the phase transformation temperature to limit the phase transformation to the outer shell of the modified zeolite particles.

A small particle size modified aluminosilicate zeolite comprising modified zeolite particles having a phase transformed outer shell, said modified zeolite particles having a water content of less than 10 weight percent, said modified zeolite particles maintaining reactivity toward acid species, formed by a process comprising the following steps:

• preparing a solution of sodium silicate;
• preparing a solution of sodium aluminate;
• preparing a solution of sodium hydroxide;
• preparing a solution of zinc chloride;
• adding the sodium hydroxide solution to the sodium aluminate solution;
• adding the sodium hydroxide/sodium aluminate solution and the zinc chloride solution to the sodium silicate solution allowing the resulting mixture to age without mixing for 0.1 to 48 hours prior to a crystallization step;
• crystallizing zeolite particles;
• heating the zeolite particles to a temperature above a phase transformation temperature of the zeolite particles causing the crystalline outer shell to be modified thereby forming said modified zeolite particles, and
• cooling the modified zeolite particles below the phase transformation temperature to limit the phase transformation to the outer shell of the modified zeolite particles.