US3969626A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for detecting total reduced sulfur
Assignee: Ametek Inc
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Filing: 1975-02-18
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Granted: 1976-07-13
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Expires: 1995-02-18
Abstract
Abstract Disclosed herein is a method for detecting total reduced sulfur in a sample gas, comprising the steps of: introducing sample gas into a sample cell, passing detecting radiation of a wavelength between about 250 and about 330 nm. through the sample gas, detecting the intensity of the detecting radiation passing through the sample gas, introducing an oxygen-containing gas into the cell to form a gas mixture with a sample gas, heating the gas mixture to a temperature above about 200°C., passing the detecting radiation through the heated gas mixture in the cell, and detecting the intensity of the detecting radiation passing through the gas mixture. The difference between the intensity of the detecting radiation passing through the gas mixture and that passing through the sample gas alone is indicative of the total reduced sulfur content of the sample gas. An apparatus to practice the above method is also disclosed.
Inventors
- 👤 Robert S. Saltzman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:55
CPC Classifications
G; G01; G01N; G01N31/00; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/33
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
192 words
A method for determining the total reduced sulfur content of a gas comprising the steps of: a. introducing a sample of the gas into a sample cell; b. passing detecting radiation of a wavelength between about 250 to about 330 nm. through the gas sample in the cell, said detecting radiation being of a wavelength strongly absorbed by SO 2 ; c. measuring the intensity of the detecting radiation passing through the gas sample; d. sealing the gas sample in the cell; e. introducing an oxygen-containing gas into the cell to form a gas mixture containing oxygen and the gas sample, said gas mixture being retained in the cell; f. thereafter heating the gas mixture to a temperature above about 200°C. to oxidize the total reduced sulfur in the gas sample; g. passing the detecting radiation through the heated gas mixture in the cell; and h. measuring the intensity of the detecting radiation passing through the gas mixture; the difference between the intensity of the detecting radiation passing through the gas mixture and that passing through the gas sample alone being indicative of the total reduced sulfur content of the sample gas.
Claim 2
Independent Claim
192 words
A method for determining the total reduced sulfur content of a gas comprising the steps of: a. introducing a sample of the gas into a sample cell; b. passing detecting radiation of a wavelength between about 250 to about 330 nm. through the gas sample in the cell, said detecting radiation being of a wavelength strongly absorbed by SO 2 ; c. measuring the intensity of the detecting radiation passing through the gas sample; d. sealing the gas sample in the cell; e. introducing an oxygen-containing gas into the cell to form a gas mixture containing oxygen and the gas sample, said gas mixture being retained in the cell; f. thereafter heating the gas mixture to a temperature above about 200°C. to oxidize the total reduced sulfur in the gas sample; g. passing the detecting radiation through the heated gas mixture in the cell; and h. measuring the intensity of the detecting radiation passing through the gas mixture; the difference between the intensity of the detecting radiation passing through the gas mixture and that passing through the gas sample alone being indicative of the total reduced sulfur content of the sample gas.
Claim 3
Dependent Claim
99 words
The method of claim 1 wherein said cell is a flow cell and wherein: a. the step of introducing gas sample into the cell is accomplished by allowing the gas sample to pass continuously through the cell; and b. the step of introducing an oxygen-containing gas into the cell to form a gas mixture is accomplished by first closing off one end of the flow cell, then closing off the remaining ends of the flow cell to contain the gas sample in the flow cell, and then introducing the oxygen-containing gas into the cell to form a gas mixture.
Claim 4
Dependent Claim
30 words
The method of claim 2 further comprising the steps of purging the sample cell of the gas mixture, cooling the cell, and repeating the procedure set forth in claim 2.
Claim 5
Dependent Claim
26 words
The method of claim 3 wherein the step of introducing an oxygen-containing gas into the cell is accomplished by introducing substantially pure oxygen into the cell.
Claim 6
Dependent Claim
16 words
The method of claim 4 wherein gas mixture is heated to a temperature above about 500°C.
Claim 7
Dependent Claim
43 words
The method of claim 4 further comprising the step of generating an electrical signal proportional to the difference between the intensity of the detecting radiation passing through the gas mixture and the intensity of the detecting radiation passing through the gas sample alone.
Claim 8
Dependent Claim
35 words
The method of claim 4 wherein, in addition to detecting radiation, reference radiation is passed through the gas mixture in the cell, said reference radiation being of a wavelength weakly absorbed by SO 2 .
Claim 9
Independent Claim
248 words
An apparatus for determining the amount of total reduced sulfur in a sample gas comprising: a. a flow cell having windows transparent at least to radiation of a wavelength in the range of about 250 to about 330 nm.; b. an inlet for introducing a sample of the gas into said cell; c. means to form said cell into a gas-tight cell to retain said gas sample; d. an inlet for introducing an oxygen-containing gas into said cell to form a gas mixture containing oxygen and the sample gas; e. a radiation source disposed adjacent to one of said windows, said radiation source comprising means for passing detecting radiation of a wavelength in the range of about 250 to about 330 nm. through said cell; said detecting radiation being of a wavelength strongly absorbed by SO 2 ; f. a detector disposed adjacent to another of said windows, said detector being responsive to the intensity of the radiation passing through said cell; g. a heater associated with said cell to raise the temperature of the gas mixture in the cell to above about 200°C. in a time less than about two minutes and allow oxidation of the total reduced sulfur in the gas sample; and h. means to generate a signal proportional to the difference between the intensity of the radiation passing through the cell when it contains the gas mixture and the intensity of the radiation passing through the cell when it contains only the gas sample.
Claim 10
Independent Claim
248 words
An apparatus for determining the amount of total reduced sulfur in a sample gas comprising: a. a flow cell having windows transparent at least to radiation of a wavelength in the range of about 250 to about 330 nm.; b. an inlet for introducing a sample of the gas into said cell; c. means to form said cell into a gas-tight cell to retain said gas sample; d. an inlet for introducing an oxygen-containing gas into said cell to form a gas mixture containing oxygen and the sample gas; e. a radiation source disposed adjacent to one of said windows, said radiation source comprising means for passing detecting radiation of a wavelength in the range of about 250 to about 330 nm. through said cell; said detecting radiation being of a wavelength strongly absorbed by SO 2 ; f. a detector disposed adjacent to another of said windows, said detector being responsive to the intensity of the radiation passing through said cell; g. a heater associated with said cell to raise the temperature of the gas mixture in the cell to above about 200°C. in a time less than about two minutes and allow oxidation of the total reduced sulfur in the gas sample; and h. means to generate a signal proportional to the difference between the intensity of the radiation passing through the cell when it contains the gas mixture and the intensity of the radiation passing through the cell when it contains only the gas sample.
Claim 11
Dependent Claim
25 words
The apparatus of claim 8 wherein said cell is a quartz sample cell and wherein said means to heat said cell is an infrared heater.
Claim 12
Dependent Claim
33 words
The apparatus of claim 9 wherein said means to heat said cell is a means to heat said cell to a temperature above about 500°C. in a time less than about 2 minutes.
Claim 13
Dependent Claim
62 words
The apparatus of claim 10 wherein said radiation source further comprises means for passing reference radiation through said cell, said reference radiation being of a wavelength weakly absorbed by SO 2 , and wherein said means for detecting the intensity of the radiation passing through said cell comprises means for separately detecting the intensity of the detecting radiation and the reference radiation.
Claim 14
Dependent Claim
19 words
The apparatus of claim 11 further comprising means for controlling the pressure of the gas mixture within said cell.
Claim 15
Dependent Claim
29 words
The apparatus of claim 11 further comprising means to electrically suppress to zero the intensity of the radiation passing through the cell when it contains only the gas sample.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-13 | 1980-01-12 | 1980-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-13 | 1984-01-12 | 1984-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-13 | 1988-01-12 | 1988-07-13 | $7700.00 | Window Closed / Lapsed |