A STUDY OF EQUILIBRIA INVOLVED BETWEEN DAREX OFF-GASES AND SOLUTIONS. Final Technical Report. Project No. A-427
A method for the quantitative analysis of aqua regia offgases by combined spectrophotometric and chromatographic techniques was developed and used to analyze aqua regia off-gases. The percentages of nitrous oxide, nitric oxide, nitrogen dioxide, nitrosyl chloride, and hydrogen chloride were obtained by measuring the infrared transmission of the gaseous sample in a 10-cm cell with silver chloride windows. The wavelengths found to be appropriate for these gases were 2.888, 5.234, 3.228, and 6.119, 4.725, and 3.556 - , respectively. The chlorine fraction was determined in carbon tetrachloride solution at 335 m - by visible-region spectrophotometry after an aliquot of gas had been shaken with saturated sodium sulfate solution to dissolve the other gases that absorb visible light. An additional gas sample was bubbled through water to remove the soluble gases and was then analyzed for hydrogen, nitrogen, and oxygen by gas chromatography on a molecular sieve column. Efforts were concentrated on analyzing the off-gases from 5M nitric acid: 2M hydrochloric acid and 2M nitric acid: 5M hydrochloric acid (the aqua regia concentrations used at Oak gas chromatography on a molecular sieve column. Efforts were concentrated on analyzing the off-gases from 5M nitric acid: 2M hydrochloric acid and 2M nitric acid: 5M hydrochloric acid (the aqua regia concentrations used at Oak Ridge) boiling at no reflux, at high reflux, and when 304 stainless steel was being dissolved in them. The off-gases from the two aqua regia compositions alone consisted essentizlly of nitrosyl chloride, water, and chlorine. When stainless steel was dissolved in these acids, hydrogen, nitric oxide, nitrous oxide, nitrogen, and nitrogen dioxide were also evolved. The concentration of hydrogen was found to be considerably higher in off-gases from the 2M nitric acid : 5M hydrochloric acid mixture than in off-gases from the 5M nitric acid: 2M hydrochloric acid mixture (0.9 to 8.6% as opposed to 0.2 to 0.5%). The yield of hydrogen per gram of steel was 0.002 g for the 2:5 aqua regia and only 0.0001 g for the 5:2 aqua regia. (auth)
- Research Organization:
- Georgia Inst. of Tech., Atlanta. Engineering Experiment Station
- NSA Number:
- NSA-15-008881
- OSTI ID:
- 4093060
- Report Number(s):
- TID-6501
- Country of Publication:
- United States
- Language:
- English
Similar Records
LOW TEMPERATURE PROCESS FOR THE REMOVAL AND RECOVERY OF CHLORIDES AND NITRATES FROM AQUEOUS NITRATE SOLUTIONS
A STUDY OF EQUILIBRIA INVOLVED BETWEEN DAREX OFF-GASES AND SOLUTIONS. Annual Report No. 1 for December 1, 1958 through July 31, 1959
Related Subjects
ADSORPTION
BOILING
CARBON TETRACHLORIDE
CHEMISTRY
CHLORIDES
CHLORINE
CHROMATOGRAPHY
DAREX PROCESS
GASES
HYDROCHLORIC ACID
HYDROGEN
HYDROGEN CHLORIDES
INFRARED RADIATION
MEASURED VALUES
MIXING
MOLECULAR SIEVES
MOLECULES
NITRIC ACID
NITROGEN
NITROGEN OXIDES
OXYGEN
PHOTOMETRY
QUANTITATIVE ANALYSIS
SILVER CHLORIDES
SODIUM SULFATES
SOLUTIONS
SPECTRA
STAINLESS STEELS
STEELS
WATER
WINDOWS