US4345976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for separating mixtures of substances of low volatility
Assignee: Individual
•
Filing: 1979-02-07
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Granted: 1982-08-24
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Expires: 1999-02-07
Abstract
Abstract The invention involves a process for substantially separating the components of mixtures of substances at least one of which is of low volatility while the other is of low or no volatility, the process using a compressed gas under supercritical conditions and an entrainer which increases the concentration of said mixture in the gaseous phase as well as the separation factor between the components to be separated. The process operates in two distillation zones the first of which substantially separates the components of low volatility in a process similar to a rectification process while the second distillation zone separates the top product of the first distillation zone from the gas with the aid of the entrainer which is condensed partially and in this state is passed in countercurrent to the gas carrying the separated component of low volatility.
Inventors
- 👤 Siegfried Peter
- 👤 Gerd Brunner
- 👤 Rolf Riha
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 04:46
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/43; C07C51/44; C07C51/46; B; B01; B01D; B01D11/00; B01D11/04; B01D11/0403; B01D11/0407; B01D3/00; B01D3/34; B01D3/40; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/54
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
260 words
A process for substantially separating the components of mixtures of substances at least one of which is of low volatility, while the other is of low or no volatility by using a compressed gas under supercritical conditions, and an entrainer adapted to increase the concentration of said mixtures of substances in the gaseous phase as well as the separation factor between the components to be separated, comprising in combination, feeding such mixture and said entrainer into a first distillation zone, passing said compressed gas upward through said distillation zone, effecting the separation and downward travel of the first component mixed with entrainer, to the bottom of said first distillation zone; passing from the top of said first distillation zone, the compressed gas, entrainer and second component to a point at most as high as the center of a second distillation zone, passing said compressed gas, entrainer and second component upward past a condensing zone at the top of said second distillation zone condensing part of said entrainer so it will travel downward in countercurrent to the compressed gas whereby to substantially free the same from the second component, and to pass to the bottom of said second distillation zone; recycling the compressed gas from the top of the second distillation zone to the bottom of the first distillation zone, recycling part of the bottom product of said second distillation zone to the top of said first distillation zone, whereby to effect substantial separation of said components in the absence of any substantial pressure decrease and the consequent need for recompression.
Claim 2
Dependent Claim
260 words
A process for substantially separating the components of mixtures of substances at least one of which is of low volatility, while the other is of low or no volatility by using a compressed gas under supercritical conditions, and an entrainer adapted to increase the concentration of said mixtures of substances in the gaseous phase as well as the separation factor between the components to be separated, comprising in combination, feeding such mixture and said entrainer into a first distillation zone, passing said compressed gas upward through said distillation zone, effecting the separation and downward travel of the first component mixed with entrainer, to the bottom of said first distillation zone; passing from the top of said first distillation zone, the compressed gas, entrainer and second component to a point at most as high as the center of a second distillation zone, passing said compressed gas, entrainer and second component upward past a condensing zone at the top of said second distillation zone condensing part of said entrainer so it will travel downward in countercurrent to the compressed gas whereby to substantially free the same from the second component, and to pass to the bottom of said second distillation zone; recycling the compressed gas from the top of the second distillation zone to the bottom of the first distillation zone, recycling part of the bottom product of said second distillation zone to the top of said first distillation zone, whereby to effect substantial separation of said components in the absence of any substantial pressure decrease and the consequent need for recompression.
Claim 3
Dependent Claim
34 words
A separation process according to claim 1, wherein the compressed gas used under supercritical conditions, is characterized by the fact that its critical temperature is lower than any temperature prevailing during the separation process.
Claim 4
Dependent Claim
71 words
A separation process according to claim 1, wherein the entrainer is characterized by the act that its critical temperature is higher than any temperature prevailing during the separation process, and the further fact that together with gas used under supercritical conditions, it forms a binary system the phase boundary line of which in the pressure-concentration diagram at the working temperatures and pressures prevailing during the separation process, forms a closed loop.
Claim 5
Dependent Claim
45 words
A separation process according to claim 1, wherein the substances in the mixtures to be separated include at least one substance of low volatility and another of low or no volatility, said substances preferably being selected from the class consisting of organic and inorganic compounds.
Claim 6
Dependent Claim
42 words
A process according to claim 1 in which the entrainer is selected from the group consisting of benzene, toluene, xylene, acetonitrile, acetone, methylene chloride, cyclohexane, hexane, n-heptane, methyl cyclohexane, iso-octane, octane, nonane, decane, furan, 2-methylfuran, furfural, furan-3-aldehyde, ethyl furan or mixtures thereof.
Claim 7
Dependent Claim
40 words
A process according to claim 5 in which the entrainer is selected from the group consisting of toluene or xylene at a concentration of from 5 to 70 percent by weight based on the mixture of fatty acids and entrainer.
Claim 8
Dependent Claim
44 words
A process according to claim 1 for the substantial separation of saturated and unsaturated fatty acids of low volatility in which the entrainer is furan or a derivative thereof, acetonitrile, acetone, methylene chloride, n-heptane, iso-octane, cyclohexane, methyl cyclohexane, octane, nonane, decane, or mixtures thereof.
Claim 9
Dependent Claim
38 words
A process according to claim 1 for the substantial separation of glycerides of low volatility in which the entrainer is an alcohol containing up to four carbon atoms, a ketone containing up to five carbon atoms, or water.
Claim 10
Dependent Claim
39 words
A process according to claim 1, for the substantial separation of polyhydric alcohols of low volatility in which the entrainer is an alcohol containing up to four carbon atoms, a ketone containing up to five carbon atoms, or water.
Claim 11
Dependent Claim
34 words
A process according to claim 1 in which the supercritical component is selected from the group consisting of aliphatic hydrocarbons, halogen containing aliphatic hydrocarbons containing from 1 to 4 carbon atoms, or carbon dioxide.
Claim 12
Dependent Claim
25 words
A process according to claim 1 wherein the compressed gas used under supercritical conditions is ethane, propane, trifluoro-chloromethane, difluoro-dichloromethane, trifluoro-bromomethane, methyl fluoride, ethylene or propylene.
Claim 13
Dependent Claim
39 words
A separation process according to claim 1 for substantially separating a mixture of fatty acids essentially consisting of oleic acid and stearic acid, wherein the compressed gas used under supercritical conditions is carbon dioxide, and the entrainer is benzene.
Claim 14
Dependent Claim
29 words
A separation process according to claim 1 for substantially separating mono- and diglycerides, wherein the compressed gas used under supercritical conditions is carbon dioxide, and the entrainer is acetone.
Claim 15
Dependent Claim
34 words
A separation process according to claim 1 for substantially separating a mixture of glycerides and free fatty acids, wherein the compressed gas used under supercritical conditions is carbon dioxide, and the entrainer is acetone.
Claim 16
Dependent Claim
33 words
A separation process according to claim 1 for substantially separating triglycerides and lecithin contained in soja oil, wherein the compressed gas used under supercritical conditions is carbon dioxide, and the entrainer is hexane.
Claim 17
Dependent Claim
50 words
A separation process according to claim 1 for substantially separating a mixture of mineral oils of low volatlity and very small particles of clay, wherein the compressed gas used under supercritical conditions is methane, and the entrainer is a mixture of hydrocarbons with boiling temperatures between 50° and 90° C.
References Cited (Backward Citations)
US1439685A
Cited
US1965566A
Cited
US2351249A
Cited
US2838480A
Cited
US3969196A
Cited
US3378467A
Cited
US3806619A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-08-23 | 1986-02-22 | 1986-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-23 | 1990-02-22 | 1990-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-23 | 1994-02-22 | 1994-08-24 | $7700.00 | Window Closed / Lapsed |