Method of making hydroprocessing catalyst
A chelated hydroprocessing catalyst exhibiting low moisture is obtained by heating an impregnated, calcined carrier to a temperature higher than 200° C. and less than a temperature and for a period of time that would cause substantial decomposition of the chelating agent.
1. A hydroprocessing catalyst prepared according to a method comprising:
(I) providing at least the following components:
(A) at least one calcined foraminous carrier having a water pore volume;
(B) catalytically active metals useful in hydroprocessing hydrocarbons, said metals in the form of at least one component providing at least one metal from Group VIB of the periodic table and at least one component providing at least one metal from Group VIII of the periodic table;
(C) at least one chelate;
(D) water in a quantity sufficient to form a solution or dispersion comprising said catalytically active metals and said at least one chelate; and
(E) optionally, at least one phosphorus-containing acidic component;
(II) contacting said components (I)(A) with said solution or dispersion comprising (I)(B), (I)(C), (I)(D) and optionally (I)(E) for a time and at a temperature sufficient to form a mixture and to impregnate said carrier with a suitable amount of said components (I)(B) and (I)(C) and optionally (I)(E);
(III) to the extent that the volume of said solution or dispersion equals or exceeds the water pore volume of said carrier separating said impregnated carrier from said excess solution or dispersion; and
(IV) heating said impregnated carrier to a temperature higher than 200° C. and less than a temperature and for a period of time that would cause substantial decomposition of said at least one chelate;
wherein said at least one chelate compound comprises about 0.05 to about 5 times the molar amount of said catalytically active metals; and wherein said catalyst exhibits a moisture content of about 3 wt % to about 6 wt %.
2. The catalyst of claim 1 wherein said chelate compound is at least one hydroxycarboxylic acid.
3. The catalyst of claim 2 wherein said at least one hydroxycarboxylic acid is citric acid.
4. The catalyst of claim 1 useful in hydroprocessing a petroleum feed, wherein said hydroprocessing comprises hydrodesulfurization and hydrodenitrification of hydrocarbons.
5. The catalyst of claim 1 useful in hydrodesulfurization and hydrodenitrification of hydrocarbons.