Solutions and catalysts comprising group VI metal, group VIII metal, phosphorus and an additive
This invention provides a process for forming a solution composition, which process comprises forming a primary solution by bringing together, in an aqueous medium, i) at least one phosphorus compound, ii) at least one Group VI metal compound, iii) at least one Group VIII metal compound, and iv) an additive which is a) tetraethylene glycol, b) polyethylene glycol having an average molecular weight in the range of about 200 to about 400, c) a mixture of tetraethylene glycol and polyethylene glycol having an average molecular weight in the range of about 200 to about 400, or d) a mixture of (1) tetraethylene glycol and/or polyethylene glycol having an average molecular weight in the range of about 200 to about 400 and (2) one or more of monoethylene glycol, diethylene glycol, and triethylene glycol. The molar ratio of additive to the total moles of Group VI metal and Group VIII metal is above 0.30:1, and the atomic ratio of phosphorus to Group VI metal is at least about 0.33:1. Optionally, the primary solution is heated at a temperature above about 40° C. to form a heated solution. The heated solution is optionally cooled to form a cooled solution. Also provided are compositions formed by such processes, processes for forming catalyst compositions from these compositions, and catalyst compositions formed by these processes.
1. A process for forming a solution composition, which process comprises
A) bringing together, in an aqueous medium,
i) at least one phosphorus compound,
ii) at least one Group VI metal compound,
iii) at least one Group VIII metal compound, and
iv) an additive which is
a) tetraethylene glycol,
b) polyethylene glycol having an average molecular weight in the range of about 200 to about 400,
c) a mixture of tetraethylene glycol and polyethylene glycol having an average molecular weight in the range of about 200 to about 400, or
d) a mixture of (1) tetraethylene glycol and/or polyethylene glycol having an average molecular weight in the range of about 200 to about 400 and (2) one or more of monoethylene glycol, diethylene glycol, and triethylene glycol,
where the molar ratio of additive to the total moles of Group VI metal and Group VIII metal is about 0.36:1 to about 0.6:1, and where the atomic ratio of phosphorus to Group VI metal is at least about 0.33:1,
to form a primary solution;
B) optionally heating said primary solution at a temperature above about 40° C. to form a heated solution; and
C) optionally cooling said heated solution to form a cooled solution.
2. A process as in claim 1 wherein said atomic ratio of phosphorus to Group VI metal is about 0.33:1 to about 0.8:1, and/or wherein said Group VI metal compound and the Group VIII metal compound are in an amount such that the Group VI metal and the Group VIII metal are in an atomic ratio of at least about 1.5:1.
3. A process as in claim 1 wherein said phosphorus compound is a water soluble, acidic phosphorus compound, optionally wherein said phosphorus compound is orthophosphoric acid.
4. A process as in claim 1 wherein said Group VIII metal compound is a carbonate, hydroxide, or hydroxy-carbonate, and/or wherein said Group VI metal compound is an oxide or an oxo-acid.
5. A process as in claim 1 wherein said additive is polyethylene glycol having an average molecular weight in the range of about 200 and about 400, or a mixture of triethylene glycol and tetraethylene glycol and/or polyethylene glycol having an average molecular weight in the range of about 200 to about 400.
6. A process as in claim 1 wherein an organic acid is included, which organic acid has at least one acid group and at least one functional group selected from a hydroxyl group and an acid group, optionally wherein said organic acid is citric acid.
7. A process as in claim 1 wherein said Group VI metal is molybdenum and/or tungsten, and/or wherein said Group VIII compound is a nickel or cobalt compound.
8. A composition formed as in claim 1 , which composition comprises a Group VI metal, a Group VIII metal, phosphorus, and an additive which is
a) tetraethylene glycol,
b) polyethylene glycol having an average molecular weight in the range of about 200 to about 400,
c) a mixture of tetraethylene glycol and polyethylene glycol having an average molecular weight in the range of about 200 to about 400, or
d) a mixture of (1) tetraethylene glycol and/or polyethylene glycol having an average molecular weight in the range of about 200 to about 400 and (2) one or more of monoethylene glycol, diethylene glycol, and triethylene glycol,
where the molar ratio of additive to the total moles of Group VI metal and Group VIII metal is about 0.36:1 to about 0.6:1, and where the atomic ratio of phosphorus to Group VI metal is at least about 0.33:1.
9. A composition as in claim 8 wherein said atomic ratio of phosphorus to Group VI metal is in the range of about 0.33:1 to about 0.8:1, and/or wherein said Group VI metal compound and the Group VIII metal compound are in an amount such that the Group VI metal and the Group VIII metal are in an atomic ratio of about 1.5:1 to about 6:1.
10. A composition as in claim 8 wherein said Group VI metal is molybdenum and/or tungsten, and/or wherein said Group VIII metal is nickel or cobalt.
11. A process for forming a catalyst, which process comprises
I) bringing together a carrier and an impregnation solution, which impregnation comprises a composition of claim 8 , to form an impregnated carrier; and
II) drying the impregnated carrier, and
III) optionally calcining the impregnated carrier,
to form a catalyst, and optionally sulfiding the catalyst.
12. A process as in claim 11 wherein I) comprises a single impregnation step.
13. A process as in claim 11 wherein said carrier is silica, alumina, silica-alumina, alumina with silica-alumina dispersed therein, alumina-coated silica, or silica-coated alumina.
14. A process as in claim 11 wherein at least one organic acid, which organic acid has at least one acid group and at least one functional group selected from a hydroxyl group and an acid group, is present in the impregnation solution, optionally wherein said organic acid is citric acid.
15. A process as in claim 1 wherein the molar ratio of (1) to (2) is 0.15:1 or more.