Patent US4721818A successfully refreshed from Google Patents.
US4721818A
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Purification of polyols prepared using double metal cyanide complex catalysts
Assignee: Lyondell Chemical Technology LP
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Filing: 1987-03-20
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Granted: 1988-01-26
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Expires: 2007-03-20
Abstract
Abstract A method for removing double metal cyanide complex catalyst residue from polyols using alkali metal hydrides is disclosed. In one embodiment, the catalyst residue is converted into an insoluble ionic metal species and separated by filtration using magnesium or aluminum silicate to facilitate separation.
Inventors
- 👤 Stephen D. Harper
- 👤 Stephen H. Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:35
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C07; C07C; C07C41/00; C07C41/01; C07C41/34; C07C41/44; C08G65/00; C08G65/02; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2663; C08G65/30
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
75 words
A method for removing double metal cyanide complex catalyst residue from polyols which comprises after polyol formation the steps of: (a) incorporating into the catalyst residue-containing polyol an effective amount of an alkali metal hydride to convert the double metal cyanide complex catalyst into an insoluble ionic metal species separable from the polyol wherein the polyol hydroxyl groups are also converted to alkoxide groups; and (b) separating the insoluble ionic metal species from the polyol.
Claim 2
Independent Claim
75 words
A method for removing double metal cyanide complex catalyst residue from polyols which comprises after polyol formation the steps of: (a) incorporating into the catalyst residue-containing polyol an effective amount of an alkali metal hydride to convert the double metal cyanide complex catalyst into an insoluble ionic metal species separable from the polyol wherein the polyol hydroxyl groups are also converted to alkoxide groups; and (b) separating the insoluble ionic metal species from the polyol.
Claim 3
Dependent Claim
13 words
The method of claim 1 in which said separating is accomplished by filtration.
Claim 4
Dependent Claim
28 words
The method of claim 1 in which said separating is accomplished by passing the mixture of catalyst residue-containing polyol and alkali metal hydride through an ion exchange resin.
Claim 5
Dependent Claim
14 words
The method of claim 1 in which said alkali metal hydride is sodium hydride.
Claim 6
Dependent Claim
14 words
The method of claim 1 in which said alkali metal hydride is potassium hydride.
Claim 7
Dependent Claim
19 words
The method of claim 1 in which said alkali metal hydride is a mixture of sodium and potassium hydride.
Claim 8
Dependent Claim
32 words
The method of claim 1 in which said alkali metal hydride is employed in a molar ratio of alkali metal hydride to hydroxyl groups on the polyol of from 1:1 to 1:500.
Claim 9
Dependent Claim
34 words
The method of claim 1 wherein the mixture of catalyst residue-containing polyol and alkali metal hydride prepared in step (a) is heated to enhance the speed at which the insoluble ionic metal species forms.
Claim 10
Dependent Claim
44 words
The method of claim 1 comprising after step (a) and before step (b) the step of incorporating an effective amount of ethylene oxide into the catalyst residue-containing polyol/alkali metal hydride mixture to convert the secondary hydroxyl groups of the polyol to primary hydroxyl groups.
Claim 11
Dependent Claim
32 words
The method of claim 1 wherein minor amount of aluminum silicate is introduced into the mixture and the insoluble ionic metal species is separated from the polyol in step (b) by filtration.
Claim 12
Dependent Claim
33 words
The method of claim 1 wherein a minor amount of magnesium silicate is introduced into the mixture and the insoluble ionic metal species is separated from the polyol by in step (b) filtration.
Claim 13
Dependent Claim
38 words
The method of claim 1 wherein a minor amount of a mixture of aluminum and magnesium silicate is introduced into the mixture and the insoluble ionic metal species is separated from the polyol in step (b) by filtration.
References Cited (Backward Citations)
US4355188A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-25 | 1991-07-27 | 1992-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-25 | 1995-07-27 | 1996-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-25 | 1999-07-27 | 2000-01-26 | $7700.00 | Window Closed / Lapsed |