Patent US5022967A successfully refreshed from Google Patents.
US5022967A
Expired / Lapsed
US
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Microdistillation apparatus
Assignee: Lachat Instruments Inc
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Filing: 1989-09-18
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Granted: 1991-06-11
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Expires: 2009-09-18
Abstract
Abstract A microdistillation column for the quantitative steam distillation of cyanide, phenolic compounds, hydrogen fluoride, ammonia, sulfites and other volatile analyte compounds from samples of environmental waters and sludge for their subsequent analysis involves volatilizing the water in the sample tube of the microdistillation column. The pressure which develops due to the water vapor forces all volatile compounds from the water sample, including the water itself, through a hydrophobic membrane and into the collector tube of the microdistillation column. The volatile compounds and the water vapor condense in the cooler collector tube and are quantitatively trapped and retained over the membrane. Relatively small samples may be distilled in the column.
Inventors
- 👤 Scott Stieg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:14
CPC Classifications
B; B01; B01D; B01D3/00; B01D3/34; B01D3/38; G; G01; G01N; G01N1/00; G01N1/28; G01N1/40; G01N25/00; G01N25/14; G01N1/4022; G01N2001/4033; Y; Y10; Y10S; Y10S159/00; Y10S159/27; Y10S159/28; Y10S159/41; Y10S159/42; Y10S203/00; Y10S203/02; Y10T; Y10T436/00; Y10T436/25; Y10T436/25375; Y10T436/255
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
158 words
A microdistillation apparatus for the distillation of a volumetric sample containing volatile analyte compounds, said apparatus comprising: a sample tube including means for holding the volumetric sample, said sample tube having an open top end and a closed bottom end; a collector tube having an open bottom end and top end, said open bottom end being fitted to said open end of said sample tube, said collector tube including means for holding a trapping solution; at least two hydrophobic, porous membranes, one of said membranes disposed in said collector tube in close proximity to said bottom end of said collector tube in spaced relation from the volumetric sample, said membrane permitting the volumetric sample to pass through when volatized thereby conveying a purged analyte to the trapping solution, said membrane further preventing reverse transmission of the trapping solution and condensate, the other of said two hydrophobic, porous membranes being disposed in said collector tube proximate said top end.
Claim 2
Dependent Claim
158 words
A microdistillation apparatus for the distillation of a volumetric sample containing volatile analyte compounds, said apparatus comprising: a sample tube including means for holding the volumetric sample, said sample tube having an open top end and a closed bottom end; a collector tube having an open bottom end and top end, said open bottom end being fitted to said open end of said sample tube, said collector tube including means for holding a trapping solution; at least two hydrophobic, porous membranes, one of said membranes disposed in said collector tube in close proximity to said bottom end of said collector tube in spaced relation from the volumetric sample, said membrane permitting the volumetric sample to pass through when volatized thereby conveying a purged analyte to the trapping solution, said membrane further preventing reverse transmission of the trapping solution and condensate, the other of said two hydrophobic, porous membranes being disposed in said collector tube proximate said top end.
Claim 3
Dependent Claim
19 words
The microdistillation apparatus as claimed in claim 1, wherein said collector tube is severable into at least two sections.
Claim 4
Dependent Claim
17 words
The microdistillation apparatus as claimed in claim 2, wherein one of said sections is an analysis vessel.
Claim 5
Dependent Claim
22 words
The microdistillation apparatus as claimed in claim 1, wherein said collector tube is formed of a material with a passive thermal gradient.
Claim 6
Dependent Claim
13 words
The microdistillation apparatus as claimed in claim 4, wherein said material is polypropylene.
Claim 7
Dependent Claim
23 words
The microdistillation apparatus as claimed in claim 1, further including a cap removably fit securely over said top end of said collector tube.
Claim 8
Dependent Claim
20 words
The microdistillation apparatus as claimed in claim 6, wherein said cap includes means for equalizing pressure in said collector tube.
Claim 9
Dependent Claim
29 words
The microdistillation apparatus as claimed in claim 1, wherein said open top end of said sample tube is removably fitted to said open bottom end of said collector tube.
Claim 10
Dependent Claim
29 words
The microdistillation apparatus as claimed in claim 1, wherein the pore size of said hydrophobic, porous membranes is in the range of from about 0.2 to about 0.5 micrometers.
Claim 11
Dependent Claim
16 words
The microdistillation apparatus as claimed in claim 9, wherein said pore size is about 0.4 micrometers.
Claim 12
Dependent Claim
27 words
The microdistillation apparatus as claimed in claim 1, wherein said one of said membranes is from about five thousandths to about fifteen thousandths of an inch thick.
Claim 13
Dependent Claim
39 words
The microdistillation apparatus as claimed in claim 1, wherein at least a section of said bottom end of said collector tube fits over at least a section of said top end of said sample tube, forming a seal therebetween.
Claim 14
Dependent Claim
33 words
The microdistillation apparatus as claimed in claim 12, wherein said section of said bottom end of said collector tube and said section of said top end of said sample tube are inversely chamfered.
Claim 15
Dependent Claim
37 words
The microdistillation apparatus as claimed in claim 13, wherein said one of said membranes is removably fitted to the inside circumference of said bottom end of said collector tube above said chamfered section of said sample tube.
Claim 16
Dependent Claim
28 words
The microdistillation apparatus as claimed in claim 1, further comprising a mounting ring for positioning said one of said membranes inside said bottom end of said collector tube.
Claim 17
Dependent Claim
14 words
The microdistillation apparatus as claimed in claim 1, wherein said hydrophobic membranes are polytetrafluoroethylene.
Claim 18
Dependent Claim
14 words
The microdistillation apparatus as claimed in claim 1, wherein said microdistillation column is disposable.
Claim 19
Dependent Claim
21 words
The microdistillation apparatus as claimed in claim 1, further comprising a mounting stop around the outer circumference of said sample tube.
Claim 20
Dependent Claim
20 words
The microdistillation apparatus as claimed in claim 1, further comprising means for sealing said top end of said collector tube.
Claim 21
Dependent Claim
23 words
The microdistillation apparatus as claimed in claim 19, wherein said sealing means comprises a cap having a pin hole through its top surface.
Claim 22
Dependent Claim
26 words
The microdistillation apparatus as claimed in claim 1 wherein said means for holding the volumetric sample holds a volumetric sample not greater than about 10 mL.
Claim 23
Dependent Claim
26 words
The microdistillation apparatus as claimed in claim 21, wherein said means for holding the volumetric sample holds a volumetric sample not greater than about 5 mL.
Claim 24
Dependent Claim
26 words
The microdistillation apparatus as claimed in claim 22, wherein said means for holding the volumetric sample holds a volumetric sample not greater than about 0.1 mL.
Claim 25
Dependent Claim
18 words
The microdistillation apparatus as claimed in claim 1, wherein said collector tube is provided with a break-away mark.
References Cited (Backward Citations)
US1917272A
Cited
US2608528A
Cited
US3305595A
Cited
US3340157A
Cited
US3878054A
Cited
US3303634A
Cited
US3455792A
Cited
US3776970A
Cited
US4089749A
Cited
GB1566253A
Cited
US4476024A
Cited
US4267150A
Cited
US4545862A
Cited
US4620900A
Cited
US4806313A
Cited
US4789526A
Cited
US4959197A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-10 | 1994-12-10 | 1995-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-10 | 1998-12-10 | 1999-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-10 | 2002-12-10 | 2003-06-11 | $7700.00 | Window Closed / Lapsed |