Zeolite catalysis

A process for preparing hydrocarbons boiling in the gasoline and/or distillate range by contacting a feedstock comprising lower molecular weight olefins in a reaction zone under conditions of elevated temperature and pressure with a shape selective crystalline aluminosilicate catalyst, comprising:

• reducing the non-shape selective surface-cracking and/or surface isomerization activity of the aluminosilicate catalyst by a process comprising:
• preparing an aqueous solution comprising colloidal silica, optionally an organic directing agent, and a source of hydroxide ions;
• mixing the aqueous solution with an aqueous dispersion of shape-selective crystalline aluminosilicate to form a homogeneous mixture which is subsequently heated;
• adding an aqueous solution comprising a source of fluoride ions to the homogeneous mixture to form a reactive composition;
• heating the reactive composition at a temperature to effectively form a surface-deactivated catalyst comprising a crystalline fluoride-containing silica outer shell on an aluminosilicate;
• withdrawing the surface-deactivated catalyst from the reactive composition for washing, drying, and calcining of the catalyst;
• and
• removing the catalyst to the reaction zone for contact with the olefin feedstock.