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US 4,302,206 AGranted
Apparatus and process for analysis of gaseous nitrogen trichloride
AssigneeOlin Corporation
InventorsBarry P. Profeta, David A. Shaw
Life of this patent
Estimating the term…
Abstract
Apparatus and process for analyzing the nitrogen trichloride concentration in gases containing it utilizing an ultraviolet light source. Unabsorbed filtered light collected from the sample at a wavelength of about 218 nm is compared with a standard at a wavelength of about 260 nm and the resultant is expressed in terms of nitrogen trichloride concentration.
Claims15
An apparatus for analyzing gases for nitrogen trichloride utilizing ultraviolet light comprised of:
- a. means for conveying a sample of gas to be analyzed for nitrogen trichloride to a gas analyzer system,
- b. cell having a fixed predetermined thickness through which said sample is passed during analysis,
- c. a source of ultraviolet light capable of passing ultraviolet light across said thickness through said cell to a light detector means,
- d. a first filter positioned between said cell and said light detector means, said filter permitting sample light of about 218 nm to pass to said light detector means,
- e. said light detector means being capable of measuring the amount of said sample light received from said filter and comparing it with a predetermined standard, and
- f. means for expressing said sample light in terms of concentration of nitrogen trichloride in said sample.
3 more elements
The process for analyzing nitrogen trichloride in gases containing it which comprises:
- a. passing a sample of gas to be analyzed for nitrogen trichloride from a gas generating reaction through a sample cell of predetermined fixed thickness along a flow path perpendicular to said fixed thickness,
- b. simultaneously passing ultraviolet light from an ultraviolet source through the gas sample across said predetermined fixed thickness, whereby light energy at a wavelength of about 218 nm is absorbed by nitrogen trichloride in the gas sample passing through said cell, and remaining unabsorbed light energy passes across said fixed thickness through said cell,
- c. passing said remaining unabsorbed light energy through a first filter, whereby all of the remaining unabsorbed light energy other than about 218 nm is absorbed by the filter, the remaining filtered unabsorbed light of about 218 nm passes through said filter to a light detector means,
- d. comparing said filtered unabsorbed light of about 218 nm in said light detector means with a predetermined standard of nitrogen trichloride concentration,
- e. calculating the concentration of nitrogen trichloride in said gas sample, and
- f. adjusting the reaction conditions in the gas generating reaction to maintain the concentration of nitrogen trichloride in subsequent gas samples within a predetermined range.
3 more elements
Dependencies are inferred from the claim text.