Manufacture of improved catalyst

A method for manufacture of a catalyst composition comprising the steps of:

• a) forming a slurry by combining a siliceous crystalline material (Z) having the structure of zeolite Beta, zeolite ZSM-12, or zeolite ZSM-20, with a source of phosphorus (P) and at least two compounds selected from a source of silica (S), clay (C), and a source of alumina (A) in a mixer under aqueous conditions, wherein the siliceous crystalline material (Z), the source of silica (S), the clay (C), and the source of alumina CA) are added to the slurry in the mixer in a sequence selected from SCZP, CSZP, SAZCP, ASZCP, SAZPC, ASZPC, SAPZC, ASPZC, CPZSA, PCZSA, SCZPA, CSZPA, APZSC, and PAZSC in a short-hand representation, said compounds added in amounts effective to make the weight ratio of alumina from sources other than the siliceous crystalline material to phosphorus less than about 5 and to make the weight ratio of silica from sources other than the siliceous crystalline material to alumina from sources other than the siliceous crystalline material greater than or equal to about 5;
• and
• b) spray drying the slurry at a pH greater than or equal to about 1 and less than or equal to about 5.

A method for manufacture of a catalyst composition comprising the steps of:

• a) forming a slurry by combining a siliceous crystalline material (Z) having the structure of zeolite Beta, zeolite ZSM-12, or zeolite ZSM-20, with a source of phosphorous (P) and at least two compounds selected from a source of silica (S), clay (C), and a source of alumina (A) in a mixer under aqueous conditions, said compounds added in amounts effective to make the weight ratio of alumina from sources other than the siliceous crystalline material to phosphorus less than about 5 and to make the weight ratio of silica from sources other than the siliceous crystalline material to alumina from sources other than the siliceous crystalline material greater than or equal to about 5, said compounds added in a sequence selected from SCZP, CSZP, SAZCP, ASZCP, SAZPC, ASZPC, SAPZC, ASPZC, CPZSA, PCZSA, SCZPA, CSZPA, APZSC, and PAZSC in a short-hand representation, wherein the siliceous crystalline material, the source of silica, the clay, and the source of alumina are added to the slurry in a sequence and in amounts effective to produce an attrition index of less than or equal to about 7 for the catalyst composition after the catalyst composition has been calcined;
• and
• b) spray drying the slurry at a pH greater than or equal to about 1 and less than or equal to about 5.