US4301034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silica from single phase controlled hydrolysis of silicate ester
Assignee: Phillips Petroleum Co
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Filing: 1980-05-21
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Granted: 1981-11-17
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Expires: 2000-05-21
Abstract
Abstract A method comprising combining a silicate ester and water under hydrolysis conditions in the presence of a sufficient amount of solvent that the reaction mixture remains as a single phase, adding sufficient acid neutralizing agent to form a gel and separating solvent and water from the resulting silica. In a preferred embodiment, the ester and water are added to a very small amount of solvent, the addition of water being sufficiently slow that it is added at about the rate it is used up in the hydrolysis reaction. The resulting silica does not require the washing step to remove alkali metal ions since it is not made from sodium silicate, and it has large pore structure because it can be made in a relatively concentrated solution because of the use of only a minimum amount of solvent and also because the hydrolysis is carried out under conditions wherein only a single phase is produced. The resulting silica is suitable for chromatographic columns and fillers in rubber and plastics but is of primary utility as a base for a chromium oxide catalyst because of its simplicity in production and inherent large pore volume.
Inventors
- 👤 Max P. McDaniel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:56
CPC Classifications
C; C08; C08F; C08F10/00; B; B01; B01J; B01J21/00; B01J21/06; B01J21/08; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/16; C01B33/163
Claims Analysis
Total Claims: 52
Claim 1
Independent Claim
70 words
A method comprising: combining a silicate ester and water under hydrolysis conditions in the presence of a sufficient amount of solvent such that the reaction mixture remains a single phase, after hydrolysis is essentially complete adding more water and maintaining the resulting composition at an elevated temperature to induce particle growth, thereafter adding sufficient acid neutralizing agent to form a gel, and separating water and solvent from the resulting silica.
Claim 2
Independent Claim
70 words
A method comprising: combining a silicate ester and water under hydrolysis conditions in the presence of a sufficient amount of solvent such that the reaction mixture remains a single phase, after hydrolysis is essentially complete adding more water and maintaining the resulting composition at an elevated temperature to induce particle growth, thereafter adding sufficient acid neutralizing agent to form a gel, and separating water and solvent from the resulting silica.
Claim 3
Dependent Claim
68 words
A method according to claim 1 wherein said ester and water are added slowly to a small amount of initial solvent such that the water and ester are used up in said hydrolysis about as fast as they are added and alcohol is progressively formed from the hydrolysis, thus serving as additional solvent as progressively more ester and water are added and progressively more hydrolyzed ester is formed.
Claim 4
Dependent Claim
12 words
A method according to claim 2 wherein said solvent is an alcohol.
Claim 5
Dependent Claim
19 words
A method according to claim 3 wherein said alcohol is the same as the alcohol formed from said hydrolysis.
Claim 6
Dependent Claim
33 words
A method according to claim 1 wherein said solvent is present initially in an amount of about 0.1 to 10 volume percent based on the volume of all of the ester ultimately added.
Claim 7
Dependent Claim
34 words
A method according to claim 1 wherein the amount of water added during said hydrolysis is about the stoichiometric amount needed to react with essentially all of the ester groups in said silicate ester.
Claim 8
Dependent Claim
29 words
A method according to claim 6 wherein the total amount of water added is no more than 20 times the stoichiometric amount needed to react with the ester groups.
Claim 9
Dependent Claim
18 words
A method according to claim 1 wherein said acid neutralizing agent is one of ammonia or propylene oxide.
Claim 10
Dependent Claim
14 words
A method according to claim 8 wherein said acid neutralizing agent is ammonia gas.
Claim 11
Dependent Claim
22 words
A method according to claim 8 wherein after said acid neutralizing agent is added and said gel formed, additional solvent is added.
Claim 12
Dependent Claim
26 words
A method according to claim 10 wherein after said solvent is added subsequent to said gelation, said composition is aged prior to removal of the water.
Claim 13
Dependent Claim
21 words
A method according to claim 11 wherein said aging step is carried out for a time of 1 to 2 hours.
Claim 14
Dependent Claim
27 words
A method according to claim 1 wherein said silica is dried in an air oven at a temperature at or below the boiling point of said solvent.
Claim 15
Dependent Claim
61 words
A method according to claim 1 wherein said water is removed by forming an azeotrope with said solvent and wherein a second solvent which second solvent is not miscible with water is added after said gel is formed so as to give two phases in the azeotrope so that the water can easily be separated from the solvent in the azeotrope.
Claim 16
Dependent Claim
12 words
A method according to claim 14 wherein said second solvent is toluene.
Claim 17
Dependent Claim
14 words
A method according to claim 1 wherein said hydrolysis conditions include an acid catalyst.
Claim 18
Dependent Claim
12 words
A method according to claim 16 wherein said catalyst is sulfuric acid.
Claim 19
Dependent Claim
32 words
A method according to claim 17 wherein said acid is present in an amount within the range of 0.0005 to 0.05 moles of acid per mole of water used in said hydrolysis.
Claim 20
Dependent Claim
29 words
A method according to claim 1 wherein said silicate ester is represented by the formula Si(OR) 4 where R is an alkyl group containing 1 to 6 carbon atoms.
Claim 21
Dependent Claim
16 words
A method according to claim 19 wherein said alkyl group contains 3 to 4 carbon atoms.
Claim 22
Dependent Claim
13 words
A method according to claim 20 wherein said silicate ester is tetra-n-propyl orthosilicate.
Claim 23
Dependent Claim
17 words
A method according to claim 1 wherein said solvent is a 1 to 6 carbon atom alcohol.
Claim 24
Dependent Claim
17 words
A method according to claim 20 wherein said solvent is a 3 to 4 carbon atom alcohol.
Claim 25
Dependent Claim
11 words
A method according to claim 23 wherein said solvent is 1-propanol.
Claim 26
Dependent Claim
15 words
A method according to claim 1 wherein said hydrolysis is carried out under reflux conditions.
Claim 27
Dependent Claim
15 words
A method according to claim 25 wherein no mechanical agitation is utilized after the gelation.
Claim 28
Dependent Claim
30 words
A method according to claim 1 wherein a titanium compound is added after at least a part of said hydrolysis has been carried out and before said gel is formed.
Claim 29
Dependent Claim
52 words
A method according to claim 27 wherein said titanium compound is added after said hydrolysis is essentially complete and after said addition of said titanium compound, and before said acid neutralizing agent is added, more water is added and the resulting composition is maintained at an elevated temperature to induce particle growth.
Claim 30
Dependent Claim
13 words
A method according to claim 28 wherein said titanium compound is titanium tetraisopropoxide.
Claim 31
Dependent Claim
9 words
The product produced by the process of claim 1.
Claim 32
Dependent Claim
30 words
The product of claim 30 further characterized by a pore volume within the range of 2 to 4 mL/g and a surface area of 430 to 950 m 2 /g.
Claim 33
Dependent Claim
23 words
A method according to claim 1 further characterized by adding a chromium compound to give a final product catalytically active for olefin polymerization.
Claim 34
Dependent Claim
32 words
A method according to claim 32 wherein said chromium is added in an amount sufficient to give 0.1 to 5 weight percent chromium based on the weight of the final activated catalyst.
Claim 35
Dependent Claim
19 words
A method according to claim 33 wherein said chromium is added during or after hydrolysis and prior to gellation.
Claim 36
Dependent Claim
17 words
A method according to claim 34 wherein said chromium is added in the form of chromium(III) acetate.
Claim 37
Dependent Claim
24 words
A method according to claim 34 wherein a titanium compound is also added to give a tergel said titanium being added before the chromium.
Claim 38
Dependent Claim
21 words
A method according to claim 32 wherein said chromium is added after gelation and before said water and solvent are separated.
Claim 39
Dependent Claim
19 words
A method according to claim 37 wherein said chromium compound is selected from chromium(III) acetate and CrO 3 .
Claim 40
Dependent Claim
20 words
A method according to claim 32 wherein said chromium is added anhydrously after said water and solvent have been separated.
Claim 41
Dependent Claim
9 words
The product produced by the process of claim 32.
Claim 42
Dependent Claim
30 words
The product of claim 40 further characterized by a pore volume within the range of 2 to 4 mL/g and a surface area of 430 to 950 m 2 /g.
Claim 43
Independent Claim
230 words
A method of producing a catalyst comprising: combining a silicate ester of the formula Si(OR) 4 wherein R is a 3 to 4 carbon atom alkyl group, and water by slowly adding said ester and said water to a solvent-water-sulfuric acid catalyst mixture which mixture contains said solvent in an amount within the range of 0.1 to 10 volume percent based on the total volume of all of the ester ultimately to be added, said solvent being a 3 or 4 carbon atom alcohol, said water and ester being added slowly so that the water and ester are used up in said hydrolysis about as fast as they are added, alcohol progressively formed from the hydrolysis then serving as the solvent as progressively more ester and water are added and progressively more hydrolyzed ester is formed, the total amount of water being about a stoichiometric amount needed to react with the available ester groups, said hydrolysis being carried out at about reflux temperature, after said hydrolysis is complete adding an alcohol soluble titanium compound, thereafter adding additional water and holding at an elevated temperature for 1 to 5 hours to permit particle growth, adding a chromium compound soluble in the reaction mixture and thereafter introducing ammonia to bring about gelation, thereafter aging at reflux temperature for 1 to 2 hours, removing the water and solvent and drying the resulting silica.
Claim 44
Independent Claim
230 words
A method of producing a catalyst comprising: combining a silicate ester of the formula Si(OR) 4 wherein R is a 3 to 4 carbon atom alkyl group, and water by slowly adding said ester and said water to a solvent-water-sulfuric acid catalyst mixture which mixture contains said solvent in an amount within the range of 0.1 to 10 volume percent based on the total volume of all of the ester ultimately to be added, said solvent being a 3 or 4 carbon atom alcohol, said water and ester being added slowly so that the water and ester are used up in said hydrolysis about as fast as they are added, alcohol progressively formed from the hydrolysis then serving as the solvent as progressively more ester and water are added and progressively more hydrolyzed ester is formed, the total amount of water being about a stoichiometric amount needed to react with the available ester groups, said hydrolysis being carried out at about reflux temperature, after said hydrolysis is complete adding an alcohol soluble titanium compound, thereafter adding additional water and holding at an elevated temperature for 1 to 5 hours to permit particle growth, adding a chromium compound soluble in the reaction mixture and thereafter introducing ammonia to bring about gelation, thereafter aging at reflux temperature for 1 to 2 hours, removing the water and solvent and drying the resulting silica.
Claim 45
Dependent Claim
36 words
A method according to claim 42 comprising in addition activating the silica resulting after said water and solvent have been separated by heating in air at a temperature within the range of 315° to 760° C.
Claim 46
Dependent Claim
20 words
A method according to claim 43 wherein said chromium compound is chromium(III) acetate and said titanium compound is titanium tetraisopropoxide.
Claim 47
Dependent Claim
24 words
A method according to claim 44 wherein said water is removed by azeotropic distillation and said drying is carried out in an air oven.
Claim 48
Dependent Claim
18 words
A method according to claim 45 wherein said ester is tetra-n-propyl orthosilicate, and said solvent is n-propyl alcohol.
Claim 49
Dependent Claim
9 words
The product produced by the process of claim 46.
Claim 50
Dependent Claim
9 words
The product produced by the process of claim 42.
Claim 51
Independent Claim
85 words
A method comprising slowly adding a silicate ester and water to a small amount of solvent under hydrolysis conditions such that the water and ester are used up in said hydrolysis about as fast as they are added and alcohol is progressively formed from the hydrolysis, thus serving as additional solvent as progressively more ester and water are added and progressively more hydrolyzed ester is formed, thereafter adding sufficient acid neutralizing agent to form a gel, and separating water and solvent from the resulting gel.
Claim 52
Independent Claim
85 words
A method comprising slowly adding a silicate ester and water to a small amount of solvent under hydrolysis conditions such that the water and ester are used up in said hydrolysis about as fast as they are added and alcohol is progressively formed from the hydrolysis, thus serving as additional solvent as progressively more ester and water are added and progressively more hydrolyzed ester is formed, thereafter adding sufficient acid neutralizing agent to form a gel, and separating water and solvent from the resulting gel.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-16 | 1985-05-18 | 1985-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-16 | 1989-05-18 | 1989-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-16 | 1993-05-18 | 1993-11-17 | $7700.00 | Window Closed / Lapsed |