Loading patent…
AssigneeRhone-Poulenc Chimie
InventorsAlain Bouruetaubertot, Thierry Chopin, Olivier Touret
Estimating the term…
Porous alumina-based compositions having high specific surface areas, well adopted for catalyst applications and prepared by precipitation/hydrothermal treatment/calcination technique, comprise an alumina matrix having from 10% to 50% by weight of at least one rare earth or alkaline earth metal second element dispersed therein, having a pore volume, corresponding to pores of a diameter less than 100 nm, ranging from 1.2 cm.sup.3 /g, at least 80% of which corresponding to pores having a diameter ranging from 10 nm to 100 nm, after heat treatment at a temperature of 350.degree. C. and having a pore volume, also corresponding to pores of a diameter less than 100 nm, ranging from 0.6 cm.sup.3 /g to 1.5 cm.sup.3 /g, at least 90% of which corresponding to pores having a diameter ranging from 20 nm to 100 nm, after heat treatment at a temperature of 1,200.degree. C. for four hours.
A porous alumina-based composition of matter, comprising an alumina matrix having from 10% to 50% by weight of at least one rare earth or alkaline earth metal second element dispersed therein, having a pore volume, corresponding to pores of a diameter less than 100 nm, ranging from 1.2 cm.sup.3 /g to 3 cm.sup.3 /g, at least 80% of which corresponding to pores having a diameter ranging from 10 nm to 100 nm, after heat treatment at a temperature of 350.degree. C., and having a pore volume, also corresponding to pores of a diameter less than 100 nm, ranging from 0.6 cm.sup.3 /g to 1.5 cm.sup.3 /g, at least 90% of which corresponding to pores having a diameter ranging from 20 nm to 100 nm, after heat treatment at a temperature of 1,200.degree. C. for four hours.
A process for the preparation of a porous alumina-based composition of matter, comprising an alumina matrix having from 10% to 50% by weight of at least one rare earth or alkaline earth metal second element dispersed therein, having a pore volume, corresponding to pores of a diameter less than 100 nm, ranging from 1.2 cm.sup.3 /g to 3 cm.sup.3 /g, at least 80% of which corresponding to pores having a diameter ranging from 10 nm to 100 nm, after heat treatment at a temperature of 350.degree. C., and having a pore volume, also corresponding to pores of a diameter less than 100 nm, ranging from 0.6 cm.sup.3 /g to 1.5 cm.sup.3 /g, at least 90% of which corresponding to pores having a diameter ranging from 20 nm to 100 nm, after heat treatment at a temperature of 1,200.degree. C. for four hours, comprising (a) admixing a solution which includes at least one soluble compound of aluminum and at least one soluble compound of said at least one rare earth or alkaline earth metal with a solution of precipitation which includes hydroxyl ions and carbonate, oxalate and/or carboxyl ions, (b) separating therefrom the precipitate thus formed wherein alumina is in amorphous form, (c) hydrothermally treating said separated precipitate and transforming the amorphous alumina to pseudoboehmite form, (d) optionally drying the hydrothermally treated precipitate, and (e) calcining such precipitate.
A porous alumina-based composition of matter, comprising an alumina matrix having from 10% to 50% by weight of at least one rare earth or alkaline earth metal second element dispersed therein, having a pore volume, corresponding to pores of a diameter less than 100 nm, ranging from 1.2 cm.sup.3 /g to 3 cm.sup.3 /g, at least 80% of which corresponding to pores having a diameter ranging from 10 nm to 100 nm, after heat treatment at a temperature of 350.degree. C., and having a pore volume, also corresponding to pores of a diameter less than 100 nm, ranging from 0.6 cm.sup.3 /g to 1.5 cm.sup.3 /g, at least 90% of which corresponding to pores having a diameter ranging from 20 nm to 100 nm, after heat treatment at a temperature of 1,200.degree. C. for four hours, said second element being distributed in the form of small crystallites in the alumina matrix.
A porous alumina-based composition of matter, comprising an alumina matrix having from 10% to 50% by weight of at least one rare earth or alkaline earth metal second element dispersed therein, having a pore volume, corresponding to pores of a diameter less than 100 nm, ranging from 1.2 cm.sup.3 /g to 3 cm.sup.3 /g, at least 80% of which corresponding to pores having a diameter ranging from 10 nm to 100 nm, after heat treatment at a temperature of 350.degree. C., and having a pore volume, also corresponding to pores of a diameter less than 100 nm, ranging from 0.6 cm.sup.3 /g to 1.5 cm.sup.3 /g, at least 90% of which corresponding to pores having a diameter ranging from 20 nm to 100 nm, after heat treatment at a temperature of 1,200.degree. C. for four hours, a major amount of said alumina matrix having a pseudo-boehmite crystalline structure and said second element being distributed in the form of small crystallites in the alumina matrix.
Dependencies are inferred from the claim text.