US4098992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for continuous soluble polypropylene recovery from hydrocarbon polymerization media
Assignee: BP Corp North America Inc
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Filing: 1976-08-09
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Granted: 1978-07-04
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Expires: 1996-08-09
Abstract
Abstract Polypropylene is recovered from a dilute solution in spent organic polymerization medium in a process comprising: (1) partial steam stripping of volatile components from said medium to form an aqueous phase and a concentrated, water-insoluble phase containing the soluble polypropylene: (2) separating said concentrated water-insoluble phase and leading it into an evaporator: (3) evaporating the remaining volatile components from the separated said water-insoluble phase leaving fluidized polypropylene which when drawn off and solidified is suitable for commercial use.
Inventors
- 👤 Benjamin P. Belles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:40
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/06; C08J11/08; C08F; C08F6/00; C08F6/06; C08F6/12; C08J2323/00; C08J2323/02; C08J2323/10; C08J2323/12; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/62
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
149 words
A method for the continuous recovery of soluble polypropylene, having a number average molecular weight in excess of 5,000, from spent polymerization media comprising: a. Steam stripping at a temperature between about 160° F. and about 250° F. under a pressure between about 4 and about 25 psig said media to form a two-phase system comprising an organic phase and an aqueous phase wherein said organic phase comprises between about 50 and 70 weight percent soluble polypropylene; b. decanting said organic phase from said aqueous phase while at a temperature and at a pressure of about said temperature and said pressure of said steam stripping, respectively; and c. removing essentially all remaining volatile material from said organic phase by heating said organic phase to between about 300° F. and 475° F. by means of a heat transfer whereby there is recovered polypropylene of sufficient fluidity to be readily transferred.
Claim 2
Independent Claim
149 words
A method for the continuous recovery of soluble polypropylene, having a number average molecular weight in excess of 5,000, from spent polymerization media comprising: a. Steam stripping at a temperature between about 160° F. and about 250° F. under a pressure between about 4 and about 25 psig said media to form a two-phase system comprising an organic phase and an aqueous phase wherein said organic phase comprises between about 50 and 70 weight percent soluble polypropylene; b. decanting said organic phase from said aqueous phase while at a temperature and at a pressure of about said temperature and said pressure of said steam stripping, respectively; and c. removing essentially all remaining volatile material from said organic phase by heating said organic phase to between about 300° F. and 475° F. by means of a heat transfer whereby there is recovered polypropylene of sufficient fluidity to be readily transferred.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein step (c) is carried out using a thin film, wiped surface evaporator.
Claim 4
Dependent Claim
16 words
The method of claim 1 wherein the major component of said spent polymerization media is hexane.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein the polymerization diluent contained in said media is recovered and reutilized.
Claim 6
Independent Claim
152 words
A method for the continuous recovery of soluble polypropylene, having a number average molecular weight in excess of 5,000, from spent polymerization media consisting essentially of: a. Steam stripping at a temperature between about 160° F. and about 250° F. under a pressure between about 4 and about 25 psig said media to form a two-phase system comprising an organic phase and an aqueous phase wherein said organic phase comprises between about 40 and 70 weight percent soluble polypropylene; b. decanting said organic phase from said aqueous phase while at a temperature and at a pressure of about said temperature and said pressure of said steam stripping, respectively; and c. removing essentially all remaining volatile material from said organic phase by heating said organic phase to between about 300° F. and 475° F. by means of a heat transfer surface whereby there is recovered polypropylene of sufficient fluidity to be readily transferred.
Claim 7
Independent Claim
152 words
A method for the continuous recovery of soluble polypropylene, having a number average molecular weight in excess of 5,000, from spent polymerization media consisting essentially of: a. Steam stripping at a temperature between about 160° F. and about 250° F. under a pressure between about 4 and about 25 psig said media to form a two-phase system comprising an organic phase and an aqueous phase wherein said organic phase comprises between about 40 and 70 weight percent soluble polypropylene; b. decanting said organic phase from said aqueous phase while at a temperature and at a pressure of about said temperature and said pressure of said steam stripping, respectively; and c. removing essentially all remaining volatile material from said organic phase by heating said organic phase to between about 300° F. and 475° F. by means of a heat transfer surface whereby there is recovered polypropylene of sufficient fluidity to be readily transferred.
Claim 8
Dependent Claim
12 words
The method of claim 5 wherein said hexane is recovered and reutilized.
Claim 9
Dependent Claim
15 words
The method of claim 5 wherein the major component of said polymerization media is hexane.
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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) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |