EP0665254A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for purifying polyether polyols made with double metal cyanide catalysts
Assignee: Bayer Antwerpen NV
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Filing: 1995-01-20
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Granted: —
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Expires: 2015-01-20
Abstract
Abstract An improved method for purifying poly(oxypropylene) polyol containing DMC catalyst residues in which the polyol is combined with an amount of an alkali metal compound sufficient to convert DMC residues to an insoluble species, but not sufficient to generate polyol alkoxide groups. The polyol is heated in the presence of water, and is then filtered and stripped. The method eliminates the need to use magnesium silicate in removing DMC catalysts from polyols.
Inventors
- 👤 Jude T. Ruszkay
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 08:47
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2663; C08G65/30
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
109 words
A method of purifying a poly(oxypropylene) polyol, said method comprising: (a) combining a poly(oxypropylene) polyol that contains double metal cyanide (DMC) catalyst residues with an amount of an alkali metal compound sufficient to convert the DMC catalyst residues to an insoluble species, but not sufficient to generate polyol alkoxide groups; (b) heating the polyol mixture in the absence of magnesium silicate with at least about 1.5 wt.% of water based on the amount of polyol at a temperature within the range of about 80°C to about 150°C; (c) filtering the polyol mixture to remove insoluble catalyst residues; and (d) stripping the polyol mixture to remove water from the polyol.
Claim 2
Dependent Claim
42 words
A method as claimed in claim 1 characterised in that the poly(oxypropylene) polyol has an average hydroxyl functionality within the range of about 2 to about 6, and a number average molecular weight within the range of about 500 to about 50,000.
Claim 3
Dependent Claim
42 words
A method as claimed in claim 1 characterised in that the poly(oxypropylene) polyol has an average hydroxyl functionality within the range of about 2 to about 3, and a number average molecular weight within the range of about 1,000 to about 10,000.
Claim 4
Independent Claim
34 words
A method as claimed in any one of claims 1 to 3 characterised in that the alkali metal compound is selected from alkali metals, alkali metal hydroxides, alkali metal alkoxides, and alkali metal hydrides.
Claim 5
Dependent Claim
22 words
A method as claimed in claim 4 characterised in that the alkali metal compound is selected from sodium hydroxide and potassium hydroxide.
Claim 6
Independent Claim
26 words
A method as claimed in any one of the preceding claims characterised in that the amount of alkali metal compound is less than about 1000 ppm.
Claim 7
Independent Claim
31 words
A method as claimed in any one of the preceding claims characterised in that the amount of alkali metal compound is within the range of about 50 to about 1000 ppm.
Claim 8
Independent Claim
31 words
A method as claimed in any one of the preceding claims characterised in that the amount of alkali metal compound is within the range of about 500 to about 1000 ppm.
Claim 9
Independent Claim
25 words
A method as claimed in any one of the preceding claims characterised in that the filtration is performed in the presence of a filter aid.
Claim 10
Dependent Claim
16 words
A method as claimed in claim 9 characterised in that the filter aid is diatomaceous earth.
Claim 11
Independent Claim
30 words
A method as claimed in any one of the preceding claims characterised in that the filtration is performed at a temperature within the range of about 60°C to about 150°C.
Claim 12
Dependent Claim
26 words
A method as claimed in claim 11 characterised in that the filtration is performed at a temperature within the range of about 80°C to about 130°C.
Claim 13
Independent Claim
28 words
A method as claimed in any one of the preceding claims characterised in that step (b) is conducted at a temperature of from about 100°C to about 135°C.
Claim 14
Independent Claim
37 words
A method as claimed in any one of the preceding claims characterised in that the amount of water employed in step (b) is from about 1.5 to about 3% by weight, based on the amount of polyol.
Claim 15
Independent Claim
33 words
A method as claimed in any one of the preceding claims characterised in that the water stripping is performed under vacuum at a temperature within the range of about 60°C to about 150°C.
References Cited (Backward Citations)
No citation records indexed.
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