Application of cryogenic spectroscopy to the determination of impurity concentration in coal gasifiers

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6456430

Holland, R F; Quigley, G P

A number of small molecules are soluble at low-to-moderate concentrations in the ir-transparent liquefied rare gases. As part of an effort to develop methods to measure concentrations of minor constituents in product gases from coal gasifiers, we have measured the infrared spectral absorbance of solutions produced by sampling cryogenically a mixture of gases and dissolving the sample in liquid xenon. Observations thus far include CO/sub 2/, CO, CH/sub 4/, and H/sub 2/ as major constituents and NO/sub 2/, NO, NH/sub 3/, N/sub 2/O, SO/sub 2/, and COS as minor constituents in the mixture. For low concentrations in the cold solutions, solute absorption bands are narrow, with widths at half-maximum absorbance of 1 to 10 cm/sup -1/ compared with approx. 30 to 100 cm/sup -1/ for the gas phase. The band-narrowing enhances peak absorbance and reduces spectral overlapping for easier analysis of complex mixtures. In the sampling, we remove most CO and CH/sub 4/, so that only the CO/sub 2/ interferes with the spectrum of minor constituents. In the spectra we can distinguish bands of N/sub 2/O, SO/sub 2/, COS, and NO/sub 2/ (as N/sub 2/O/sub 4/) and estimate concentrations. The sensitivity and accuracy of the cryogenic solution technique for gas analysis are not yet established; however, detection of approx. 10 ppM appears possible with a half-inch absorption cell.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6456430
• Report Number(s): LA-UR-81-1736; CONF-810607-9; ON: DE81025410
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
010600 -- Coal
Lignite
& Peat-- Properties & Composition
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400104* -- Spectral Procedures-- (-1987)
ABSORPTION SPECTROSCOPY
ALKANES
AMMONIA
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CARBON OXYSULFIDE
CHALCOGENIDES
CHEMICAL ANALYSIS
COAL GAS
COAL GASIFICATION
DISPERSIONS
ELEMENTS
FLUIDS
GASES
GASIFICATION
HYDRIDES
HYDROCARBONS
HYDROGEN
HYDROGEN COMPOUNDS
IMPURITIES
INFRARED SPECTRA
LIQUIDS
LOW TEMPERATURE
METHANE
MIXTURES
NITRIC OXIDE
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN HYDRIDES
NITROGEN OXIDES
NITROUS OXIDE
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
QUALITATIVE CHEMICAL ANALYSIS
RARE GASES
SOLUTIONS
SPECTRA
SPECTROSCOPY
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
THERMOCHEMICAL PROCESSES
XENON