Patent ID: 7641887

Claim:
A calcined alumina-based catalyst support having the following characteristics: a specific surface area measured by nitrogen adsorption isotherm, of not more than 50 m 2 /g a total pore volume measured by mercury intrusion of at least 0.3 cm 3 /gram; an at least bimodal distribution of porosity characterized by a main porosity wherein at least 80% of the total pore volume corresponds to pores larger than 15 nm and a secondary porosity characterized by the fact that at least 3% of the total pore volume corresponds to pores smaller than 12 nm; an ordered relationship between the main porosity and the secondary porosity defined by the fact that any element in the main porosity is connected either to the outside of the support particle, or to at least one element in the secondary porosity, or to the outside of the support particle and at least one element in the secondary particle.