Irregularly shaped non-spherical supported catalyst, and a process for hydroconverting heavy oil fractions

Abstract

The present invention concerns a catalyst for hydrotreating and/or hydroconverting heavy metal-containing hydrocarbon feeds, said catalyst comprising a support in the form of mainly irregular and non-spherical alumina-based agglomerates the specific shape of which results from a crushing step, and containing at least one catalytic metal or a compound of a catalytic metal from group VIB and/or group VIII (groups 8, 9 and 10 of the new periodic table notation), optionally at least one doping element selected from the group constituted by phosphorus, boron and silicon (or silica which does not form part of that which may be contained in the selected support) and halogens, said catalyst essentially being constituted by a plurality of juxtaposed agglomerates each formed by a plurality of acicular platelets, the platelets of each agglomerate generally being oriented radially with respect to each other and with respect to the centre of the agglomerate. The specific shape of the catalyst improves its performance when using it for hydroconverting/hydrotreating heavy metal-containing hydrocarbon feeds.

The invention also concerns the use of said catalyst alone or as a mixture in a fixed bed or ebullated bed reactor.

Description

FIELD OF THE INVENTION[0001]The present invention concerns a catalyst for hydrotreating and / or hydroconverting heavy metal-containing hydrocarbon feeds, said catalyst comprising a support in the form of mainly irregular and non-spherical alumina-based agglomerates the specific shape of which results from a crushing step, and comprising at least one catalytic metal or a compound of a catalytic metal from group VIB (group 6 in the new periodic table notation) and / or group VIII (groups 8, 9 and 10 of the new periodic table notation), optionally at least one doping element selected from the group constituted by phosphorus, boron and silicon (or silica which does not form part of that which may be contained in the selected support) and halogens, said catalyst essentially being constituted by a plurality of juxtaposed agglomerates each formed by a plurality of acicular platelets, the platelets of each agglomerate generally being oriented radially with respect to each other and with respec...

AI Technical Summary

Problems solved by technology

That phenomenon may thus cause premature and major deactivation of the catalyst.

Pore obstruction goes hand in hand with a gradual reduction in their diameter, which increasingly limits diffusion of molecules and accentuates the concentration gradient and thus the heterogeneity of the deposit from the periphery to the interior of the porous particles, to the point that total obstruction of the pores mouth to the exterior occurs very rapidly: access to the almost intact internal porosity of the particles is thus impossible for the reagents and the catalyst is prematurely deactivated.

Catalysts with a bimodal porosity profile are highly active, but have a poorer retention capacity than catalysts with a polymodal porosity profile.

These catalysts, however, suffer from the disadvantage of being less active as regards initial activity than bimodal catalysts for HDM (hydrodemetallization), HDAC7 (hydroconverting asphaltenes which are insoluble in n-heptane), HDCCR (hydroconverting carbo