Method for measuring water concentration in ammonia

Details Method for measuring water concentration in ammonia Method for measuring water concentration in ammonia

2006-08-15

2006-08-15

Gakh, Yelena G. (Department: 1743)

Chemistry: analytical and immunological testing

Nitrogen containing

Amine and quaternary ammonium

C436S164000, C436S052000, C436S039000

Reexamination Certificate

active

07091043

ABSTRACT:
Method and apparatus for measuring a water concentration in ammonia, comprising using ammonia having a water concentration of 10 ppm or less as a reference gas, introducing the ammonia at a constant flow rate into a multi-reflection long optical path gas cell, and measuring infrared absorption intensity of water at at least one measurement wave number in the range of from 3,500 to 4,000 cm−1, from 2,600 to 3,100 cm−1, or from 1,900 to 2,400 cm−1at which infrared absorptions of ammonia and water do not overlap.According to the present invention, analysis of water in a low concentration range of 10 ppm or less in ammonia gas and liquefied ammonia can be performed in a simple and convenient manner.

REFERENCES:
patent: 4023193 (1977-05-01), Schroter et al.
patent: 4075306 (1978-02-01), Muromura
patent: 5846386 (1998-12-01), Hoffman et al.
patent: 6040915 (2000-03-01), Wu et al.
patent: 61-095229 (1986-05-01), None
patent: 05-157689 (1993-06-01), None
patent: 08-008185 (1996-01-01), None
patent: 8-201370 (1996-09-01), None
patent: 9-142833 (1997-06-01), None
patent: 09-142833 (1997-06-01), None
patent: 10-281988 (1998-10-01), None
patent: 11-507004 (1999-06-01), None
patent: 11-509980 (1999-06-01), None
patent: WO 96/39263 (1996-12-01), None
patent: WO 96/39264 (1996-12-01), None
patent: WO 96/39265 (1996-12-01), None
Wu et al. “Quantitative Analysis of Trace Moisture in NH3 Gas with Dual-Cell Near-Infrared Diode Laser Absorption Spectroscopy”, Anal. Chem., 1998, v. 70, pp. 3315-3321.
Wu et al. “Absorption Spectrometry of Trace Moisture in Ammonia Gas with a 1371 nm Distributed-Feedback Diode Laser”, Jap. J. Appl. Phys., 1999, 38(8), 4788-4793.
Girard et al. “PPB-Level Hydrometry in Nitrogen and ESG's Using Tunable Diode Laser Spectroscopy”, The International Symposium on Semiconductor Manufacturing, Oct. 1996, pp. 325-328.
“The International Association for the Properties of Water and Steam” Gaithersburg, MD Sep. 2001.
Guillevic et al. Vapor-liquid equilibrium data for the binary system water-ammonia at 403.1 K, 453.1 K, 503.1 K up to 7.0 MPa J. Chem. Eng. Data, 30, 332 (1985).
Kästle et al. “Using Diode Laser Spectroscopy to Monitor Process Gas Purity”, Microcontamination, Nov. 1991, pp. 27-31.
Wu Shang-Qian et al, “Absorption Spectrometry of Trace Moisture in Ammonia Gas with a 1371 nm Distributed-Feedback Diode Laser”Japanese Journal of Applied Physics, vol. 38, No. 8, pp. 1478-4793, Aug. 1999, XP002139960.
Communications from European Patent Office.

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