Versatile route to zeolite single crystals with controlled mesoporosity: in situ sugar decomposition for templating of hierarchical zeolites

A method for synthesis of zeolite single crystals with controlled mesoporosity is discussed. The method involves in situ generation of the required carbon template by decomposition of a carbohydrate directly onto the silica raw material used for the synthesis of zeolite. Firstly, silica gel is impregnated to incipient wetness with a concentrated solution of sucrose. During calcination in an inert gas (Ar), the auxiliary carbon particles are then formed by decomposition of sucrose inside the silica gel. Then, a zeolite synthesis gel is formed from the carbon silica composite by addition of the base and a carbon template. The carbon is removed by combustion and the mesoporous zeolite is formed upon completion of crystallization. The method allows efficient design of the porosity, enhancing the catalyst performance. Mesoporous zeolite crystals allow efficient mass transport, maximizing the catalyst performance.