Aqueous titanation of cr/silica catalysts by the use of acetylacetonate and another ligand
A method comprising contacting a silica support with a titanium-containing solution to form a titanated silica support, wherein the titanium-containing solution comprises a solvent; a ligand comprising a glycol, a carboxylate, a peroxide, or a combination thereof, and a titanium compound having the formula Ti(acac) 2 (OR) 2 , wherein “acac” is acetylacetonate and wherein each R independently is ethyl, isopropyl, n-propyl, isobutyl, or n-butyl.
1. A pre-catalyst composition consisting of:
a) a chrominated-silica support comprising a silica wherein an amount of the silica is in a range of from about 50 wt. % to about 99 wt. % based upon a total weight of the chrominated-silica support; wherein the chrominated-silica support comprises from about 0.1 wt. % to about 20 wt. % water based upon a total weight of the chrominated-silica support and wherein an amount of a chromium is in a range of from about 0.01 wt. % to about 10 wt. % based upon a total weight of the chrominated-silica support;
b) a titanium-containing compound wherein an amount of titanium is in a range of from about 0.1 wt. % to about 10 wt. % based upon a total weight of the chrominated-silica support wherein the titanium-containing compound has a formula Ti(acac) 2 (OR) 2 , wherein “acac” is acetylacetonate and wherein each R independently is ethyl, isopropyl, n-propyl, isobutyl, or n-butyl;
c) a peroxide ligand; and
d) a solvent; wherein
the peroxide ligand is in an amount ranging from about 1 mole to about 4 moles per mole of titanium present in the pre-catalyst.
2. The pre-catalyst composition of claim 1 wherein the titanium-containing compound is titanium (IV) bis-acetylacetonate diisopropoxide.
3. The pre-catalyst composition of claim 2 wherein the peroxide ligand is an organic peroxide selected from the group consisting of dialkyl peroxides, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di-(t-butylperoxy) hexane (DHBP), diacyl peroxides, dilauroyl peroxide, dibenzoyl peroxide, peroxyesters, t-butyl peroxy-2-ethylhexanoate, OO-(t-butyl)-O-(2-ethylhexyl) peroxycarbonate, t-butyl peroxy-3,5,5-trimethylhexylhexanoate, t-butyl peroxy benzoate, diperoxyketals, diacyl peroxides, t-amyl peroxides, n-butyl-4,4-di-(t-butyl peroxy) valerate, and a combination thereof.
4. The pre-catalyst composition of claim 3 wherein the solvent comprises an aqueous fluid.
5. The pre-catalyst composition of claim 4 wherein the aqueous fluid comprises deionized water, distilled water, filtered water, or a combination thereof.
6. The pre-catalyst composition of claim 3 wherein the solvent comprises an alcohol.
7. The pre-catalyst composition of claim 6 wherein the solvent comprises methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, pentanol, hexanol, cyclohexanol, heptanol, octanol, benzyl alcohol, phenol, or a combination thereof.
8. The pre-catalyst composition of claim 2 wherein the peroxide ligand comprises hydrogen peroxide, dicumyl peroxide, benzoyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, a peroxyacid, a per-carboxylic acid, a perester, or a combination thereof.
9. The pre-catalyst composition of claim 2 wherein the chrominated-silica support has a surface area in a range of from about 100 m 2 /gram to about 1000 m 2 /gram.
10. The pre-catalyst composition of claim 1 wherein the peroxide ligand is an organic peroxide selected from the group consisting of dialkyl peroxides, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di-(t-butylperoxy) hexane (DHBP), diacyl peroxides, dilauroyl peroxide, dibenzoyl peroxide, peroxyesters, t-butyl peroxy-2-ethylhexanoate, OO-(t-butyl)-O-(2-ethylhexyl) peroxycarbonate, t-butyl peroxy-3,5,5-trimethylhexylhexanoate, t-butyl peroxy benzoate, diperoxyketals, diacyl peroxides, t-amyl peroxides, n-butyl-4,4-di-(t-butyl peroxy) valerate, and a combination thereof.
11. The pre-catalyst composition of claim 1 wherein the peroxide ligand comprises hydrogen peroxide, dicumyl peroxide, benzoyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, a peroxyacid, a per-carboxylic acid, a perester, or a combination thereof.
12. The pre-catalyst composition of claim 1 wherein the solvent comprises an aqueous fluid.
13. The pre-catalyst composition of claim 12 wherein the aqueous fluid comprises deionized water, distilled water, filtered water, or a combination thereof.
14. The pre-catalyst composition of claim 1 wherein the peroxide ligand is in an amount ranging from about 1 mole to about 2 moles per mole of titanium present in the pre-catalyst.
15. The pre-catalyst composition of claim 1 wherein the peroxide ligand comprises hydrogen peroxide.
16. The pre-catalyst composition of claim 1 wherein the solvent comprises an alcohol.
17. The pre-catalyst composition of claim 16 wherein the solvent comprises methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, pentanol, hexanol, cyclohexanol, heptanol, octanol, benzyl alcohol, phenol, or a combination thereof.
18. The pre-catalyst composition of claim 1 wherein the chrominated-silica support has a surface area in a range of from about 100 m 2 /gram to about 1000 m 2 /gram.
19. The pre-catalyst composition of claim 1 wherein the chrominated-silica support has a pore volume of greater than about 0.9 cm 3 /gram.