Hydrocarbon conversion catalyst composition

1. A dewaxing or alkylaromatics isomerization catalyst composition, which consists essentially of:

a dealuminated dried and calcined extrudate, obtained from a dried and calcined extrudate, wherein the extrudate, before drying and calcination, comprises a binder that is essentially free of alumina and which comprises both silica powder, wherein said silica powder comprises powder particles having a mean diameter between 10 μm and 200 μm, and a silica sol; EU-2 zeolite, wherein said EU-2 zeolite has a silica-to-alumina molar bulk ratio before the dealumination of said dried and calcined extrudate in the range of from 100 to 210; a plasticising agent; and water in an amount of at least 35% and not exceeding 60% by weight of the extrudate before drying and calcination; and

a catalytic metal selected from the group consisting of platinum, palladium and nickel;

wherein the dealumination of said dried and calcined extrudate is done by contacting said dried and calcined extrudate with an aqueous solution of fluorosilicate salt having a concentration of at least 0.005 mole of fluorosilicate salt/liter and at most 0.5 mole of fluorosilicate salt/liter and at a temperature in the range of from 10° C. to 120° C., and

wherein the amount of said EU-2 zeolite present in said hydroconversion catalyst composition is at least 15% wt of said hydrocarbon conversion catalyst composition; and

wherein the EU-2 zeolite is in the form of EU-2 zeolite particles, where the average aluminum concentration of the EU-2 zeolite particles is at least two times the aluminum concentration at the surface of the particles.

2. The catalyst composition according to claim 1 , wherein the zeolite content, on a dry basis, is of from 20 to 70 wt % as calculated on the total of said dewaxing or alkylaromatics isomerization catalyst composition.

3. The catalyst composition according to claim 1 , wherein said fluorosilicate salt of said fluorosilicate salt solution is represented by the formula:

(A) 2/b SiF 6

wherein ‘A’ is a metallic or non-metallic cation other than H+ having the valence ‘b’.

4. A process for converting a hydrocarbon feedstock which process comprises contacting the feedstock with a catalyst composition according to claim 1 at a temperature of from 100 to 600° C. and a pressure of from 1 to 100 bara.

5. A process according to claim 4 in which process the feedstock has a 10% distillation point greater than 343° C. measured by ASTM D-2887-93.

6. The catalyst composition according to claim 2 , wherein the plasticizing agent is selected from the group consisting of dextrose, gelatin, glucose, glues, gums, salts, waxes, starch and cellulose ethers.

7. The catalyst composition according to claim 6 , wherein said binder contains at most 2% wt alumina, based on dry weight of the binder per se.

8. The catalyst composition according to claim 7 , wherein said binder contains at most 1.1% wt alumina, based on dry weight of the binder per se.

9. The catalyst composition according to claim 8 , wherein said extrudate further comprises zeolite ZSM-12 that is present therein in an amount of at most 50% wt, based on the amount of EU-2 zeolite present.

10. The catalyst composition according to claim 9 , wherein the amount of EU-2 zeolite is at least 25% wt and at most 65% wt.

11. The catalyst composition according to claim 10 , wherein said plasticizing agent is methylcellulose or a methylcellulose derivative.

12. The catalyst composition according to claim 11 , wherein said binder contains at most 0.2% wt alumina, based on dry weight of the binder per se.