Methods of preparing a catalyst utilizing hydrated reagents
A method comprising a) contacting a solvent, a carboxylic acid, and a peroxide-containing compound to form an acidic mixture wherein a weight ratio of solvent to carboxylic acid in the acidic mixture is from about 1:1 to about 100:1; b) contacting a titanium-containing compound and the acidic mixture to form a solubilized titanium mixture wherein an equivalent molar ratio of titanium-containing compound to carboxylic acid in the solubilized titanium mixture is from about 1:1 to about 1:4 and an equivalent molar ratio of titanium-containing compound to peroxide-containing compound in the solubilized titanium mixture is from about 1:1 to about 1:20; and c) contacting a chromium-silica support comprising from about 0.1 wt. % to about 20 wt. % water and the solubilized titanium mixture to form an addition product and drying the addition product by heating to a temperature in a range of from about 50° C. to about 150° C. and maintaining the temperature in the range of from about 50° C. to about 150° C. for a time period of from about 30 minutes to about 6 hours to form a pre-catalyst.
1. A pre-catalyst composition comprising:
a chromium-containing compound; a titanium-containing compound comprising at least two carboxylic acids; and a silica support;
wherein an equivalent molar ratio of titanium-containing compound to the at least two carboxylic acids is from about 1:1 to about 1:4.
2. The pre-catalyst composition of claim 1 wherein the silica support comprises from about 0.1 wt. % to about 20 wt. % water.
3. The pre-catalyst composition of claim 1 wherein the pre-catalyst further comprises a peroxide-containing compound.
4. The pre-catalyst composition of claim 3 wherein an equivalent molar ratio of titanium in the titanium-containing compound to the peroxide-containing compound is from about 1:1 to about 1:20.
5. The pre-catalyst composition of claim 1 wherein the at least two carboxylic acids comprises a C 1 to C 15 monocarboxylic acid, a C 1 to C 15 dicarboxylic acid, a C 3 to C 15 tricarboxylic acid, a C 1 to C 15 α hydroxycarboxylic acid, or a combination thereof.
6. The pre-catalyst composition of claim 1 wherein the at least two carboxylic acids comprises acetic acid, citric acid, gluconic acid, glycolic acid, glyoxylic acid, lactic acid, malic acid, malonic acid, oxalic acid, phosphonoacetic acid, tartaric acid, glyceric acid, gluconic acid, mandelic acid, 2,4-hydroxybenzoic acid, 2,6-pyridine dicarboxylic acid, nitrotriacetic acid, α-hydroxyisobutyricacid, methylmalonic acid, phenyl malonic acid, digluconic acid, iminodiacetic acid, hydoxymethyl-2-butyric acid, or a combination thereof.
7. The pre-catalyst composition of claim 1 wherein the at least two carboxylic acids comprise a first carboxylic acid selected from the group consisting of oxalate, lactate, and glycolate, and a second carboxylic acid selected from the group consisting of methylmalonic acid, phenylmalonic acid, α-hydroxyisobutyric acid, salicylic acid, and citric acid.
8. The pre-catalyst composition of claim 1 wherein the silica support further comprises alumina.
9. The pre-catalyst composition of claim 1 wherein the silica support is characterized by a surface area of from about 100 m 2 /gram to about 1000 m 2 /gram and a pore volume of from about 1.0 cm 3 /gram to about 2.5 cm 3 /gram.