US3753656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas chromatograph
Assignee: United States Department of the Navy
•
Filing: 1971-04-07
•
Granted: 1973-08-21
•
Expires: 1991-04-07
Abstract
Abstract The inventive gas chromatograph employs the response of a flame ionization detector to test air and liquid and gaseous oxygen and nitrogen for the presence and amounts of the following impurities: total hydrocarbons, individual hydrocarbons, carbon monoxide/carbon dioxide, water and freons. The invention is portable and may be used for quality control and quality assurance testing and has a sensitivity in the range of parts per million (ppm) by volume. The invention can accept a low pressure range of gases for analysis and is designed to sample fluids at cryogenic temperatures for a direct analysis from closed piping systems. The invention further utilizes two chromatographic columns, is designed to permit carrier gas backflushing of each of these columns and further features the backflushing of one column into the other column.
Inventors
- 👤 J Matson
- 👤 R Goings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:03
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/88; Y; Y10; Y10T; Y10T436/00; Y10T436/10; Y10T436/100833; Y10T436/19; Y10T436/196666; Y10T436/20; Y10T436/204998; Y10T436/205831; Y10T436/21; Y10T436/214; Y10T436/216
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
14 words
The analysis system of claim 1 wherein said converting means comprises a nickel catalyst.
Claim 2
Dependent Claim
23 words
The analysis system of claim 1 wherein a second column contains means for converting water into hydrocarbons registrable on said flame ionization detector.
Claim 3
Dependent Claim
24 words
The analysis system of claim 3 wherein said carbon monoxide/carbon dioxide converting means comprises a nickel catalyst and said water converting means comprises CaC2.
Claim 4
Dependent Claim
28 words
The analysis system of claim 3 wherein a third column contains means for eluting individual hydrocarbons and a fourth column contains means for eluting individual hydrocarbons and freons.
Claim 5
Dependent Claim
33 words
The analysis system of claim 5 further comprising third valve means connected to said third and fourth columns for selectively backflushing said third and fourth columns either individually or one into the other.
Claim 6
Dependent Claim
52 words
The analysis system of claim 6 wherein the monitoring and recording means comprises: a strip chart recorder; an amplifier having an input terminal connected to said flame ionization detector and an output terminal connected to said recorder; and a single RC feedback network connected between the output terminal and the input terminal.
Claim 7
Dependent Claim
52 words
The analysis system of claim 1 wherein the monitoring and recording means comprises: a strip chart recorder; an amplifier having an input terminal connected to said flame ionization detector and an output terminal connected to said recorder; and a single RC feedback network connected between the output terminal and the input terminal.
Claim 8
Dependent Claim
21 words
The analysis system of claim 1 wherein said first valve means includes means for controlling the mass flow of said fluid.
Claim 9
Dependent Claim
20 words
The analysis system of claim 1 further including means for controlling the temperature of at least one of said coLumns.
Claim 10
Dependent Claim
46 words
The analysis system of claim 1 wherein said sampling means comprises: means for sampling and vaporizing cryogenic fluids; means for sampling subatmospheric gases; and fourth valve means for alternatively connecting said cryogenic fluid sampling means or said subatmospheric gas sampling means to said first valve means.
Claim 11
Dependent Claim
53 words
The analysis system of claim 11 wherein said cryogenic fluid sampling means comprises: a sample line; a vaporizing coil in said sample line; a suction pump having an inlet connected to said vaporizing coil and an outlet connected to said fourth valve means; and means for maintaining said coil at a desired temperature.
Claim 12
Dependent Claim
42 words
The analysis system of claim 12 wherein said subatmospheric gas sampling means comprises a control valve means for introducing a sample gas at subatmospheric pressure, said control valve means being connected to said sample line between said coil and said suction pump.
Claim 13
Independent Claim
111 words
A method of detecting the presence and concentrations of impurities in a sample fluid via the response of a single flame ionization detector in a chromatographic analysis system comprising the steps of: introducing a known quantity of a calibration gas having a known total hydrocarbon concentration into said flame ionization detector; monitoring and recording the response of said flame ionization detector to said calibration gas; introducing a first quantity of a sample gas into said flame ionization detector; monitoring and recording the response of said flame ionization detector to said first quantity of sample gas; determining the total hydrocarbon concentration (THC) of said first quantity of sample gas by the relation
Claim 14
Dependent Claim
72 words
The method of claim 14 including the further steps of: converting the water in a third quantity of said sample gas into acetylene; introducing said third quantity of sample gas into said flame ionization detector; monitoring and recording the response of said flame ionization detector to said third quantity of sample gas; and determining the water concentration in said sample gas by the relation Increase in THC/1.3 H2O, ppm of sample gas.
References Cited (Backward Citations)
US3009060A
Cited
US3152470A
Cited
US3206968A
Cited
US3366456A
Cited
US3236603A
Cited
US3201971A
Cited
US3298788A
Cited
US3438243A
Cited
US3527567A
Cited
US3626761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |