METHOD FOR REACTIVATING A DIESEL FUEL HYDROTREATMENT CATALYST Russian patent published in 2021 - IPC B01J38/12 B01J38/52 B01J23/882 B01J23/883 

FIELD: catalysts.

SUBSTANCE: method for reactivating a hydrotreatment catalyst relates to the petroleum refining industry, in particular, to recovery of the activity of aluminium-cobalt-molybdenum and aluminium-nickel-molybdenum diesel fuel hydrotreatment catalysts. Proposed is a method for recovery of activity of a deactivated aluminium-cobalt-molybdenum and aluminium-nickel-molybdenum hydrotreatment catalyst, characterised by the fact that the deactivated catalyst is preliminarily subjected to oxidative regeneration in optimum temperature conditions defined by the method for simultaneous thermal analysis and CHNS analysis ensuring restoration of the surface of the regenerated catalyst to at least 78 to 80% of the surface of a fresh catalyst, residual carbon content of less than 1.0 wt.%, followed by reactivation by impregnation with an aqueous solution of citric acid, diethylene glycol, and propylenecarbonate, and then sustaining in the impregnation solution for at least 2 h, tempering and drying for at least 8 h while increasing the temperature step by step to 110-120°C. The concentration of each of the reagents in the solution is from 0.5 to 2.0 mol per 1 mol of Co(Ni) in the catalyst or from 0.2 to 1 mol per mol of Co (Ni)+Mo. Produced is a hydrotreatment catalyst with an activity corresponding to or greater than the activity of a fresh catalyst, without losses in the strength relative to the initial sample regenerated in an oxidising medium.

EFFECT: recovery of the activity of a spent hydrotreatment catalyst to the level corresponding to a fresh catalyst (95+%) by the reactivation method implemented based on simple processing operations using inexpensive domestically made reagents.

5 cl, 1 tbl, 3 ex