Production of crystalline silicate catalyst having monoclinic structure

摘要

A process for producing a crystalline silicate catalyst having a monoclinic structure, the process comprising providing a crystalline silicate of the MFI-type having a silicon/aluminium atomic ratio lower than 80; treating the crystalline silicate with steam and thereafter leaching aluminium from the crystalline silicate by contact with an aqueous solution of a leachant to provide a silicon/aluminium atomic ratio in the catalyst of at least 80 whereby the catalyst has a monoclinic structure.