skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Reaction mechanism in both a CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar radio frequency plasma environment

Abstract

A radio frequency (RF) plasma system used to decompose trifluoromethane (CHF{sub 3} or HFC-23) is demonstrated. The CHF{sub 3} decomposition fractions ({eta}CHF{sub 3}) and mole fractions of detected products in the effluent gas streams of CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems, respectively, have been determined. The effects of four experimental parameters, input power, O{sub 2}/CHF{sub 3} or H{sub 2}/CHF{sub 3} ratio, operational pressure, and the CHF{sub 3} feeding concentration were investigated. The same species detected in the effluent gas streams of both CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems were CH{sub 2}F{sub 2}, CF{sub 4}, HF, and SiF{sub 4}. However, the CO{sub 2} and COF{sub 2} were detected only in the CHF{sub 3}/O{sub 2}/Ar plasma system and the CH{sub 4}, C{sub 2}H{sub 2}, and CH{sub 3}F were detected only in the CHF{sub 3}/H{sub 2}/Ar plasma system. The results of a model sensitivity analysis showed that the input power was the most influential parameter for {eta}CHF{sub 3} both in the CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems. Furthermore, the possible reaction pathways were built up and elucidated in this study. The addition of hydrogen for CHF{sub 3} decomposition can produce a significant amount ofmore » HF and the main carbonaceous byproducts were CH{sub 4} and C{sub 2}H{sub 2}. Even though the {eta}CHF{sub 3} in the CHF{sub 3}/H{sub 2}/Ar plasma system is lower than that in the CHF{sub 3}/O{sub 2}/Ar plasma system, but due to the more advantages mentioned above, a hydrogen-based RF plasma system is a better alternative to decompose CHF{sub 3}.« less

Authors:
; ; ;  [1]
  1. National Cheng Kung Univ., Tainan (Taiwan, Province of China)
Publication Date:
OSTI Identifier:
697158
Resource Type:
Journal Article
Journal Name:
Industrial and Engineering Chemistry Research
Additional Journal Information:
Journal Volume: 38; Journal Issue: 9; Other Information: PBD: Sep 1999
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 54 ENVIRONMENTAL SCIENCES; FLUORINATED ALIPHATIC HYDROCARBONS; DECOMPOSITION; PLASMA FURNACES; OXYGEN; HYDROGEN; SENSITIVITY ANALYSIS; CHEMICAL REACTION KINETICS; RF SYSTEMS; OZONE LAYER; FIRE EXTINGUISHERS; AIR POLLUTION CONTROL

Citation Formats

Wang, Y.F., Lee, W.J., Chen, C.Y., and Hsieh, L.T. Reaction mechanism in both a CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar radio frequency plasma environment. United States: N. p., 1999. Web. doi:10.1021/ie9900519.
Wang, Y.F., Lee, W.J., Chen, C.Y., & Hsieh, L.T. Reaction mechanism in both a CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar radio frequency plasma environment. United States. doi:10.1021/ie9900519.
Wang, Y.F., Lee, W.J., Chen, C.Y., and Hsieh, L.T. Wed . "Reaction mechanism in both a CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar radio frequency plasma environment". United States. doi:10.1021/ie9900519.
@article{osti_697158,
title = {Reaction mechanism in both a CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar radio frequency plasma environment},
author = {Wang, Y.F. and Lee, W.J. and Chen, C.Y. and Hsieh, L.T.},
abstractNote = {A radio frequency (RF) plasma system used to decompose trifluoromethane (CHF{sub 3} or HFC-23) is demonstrated. The CHF{sub 3} decomposition fractions ({eta}CHF{sub 3}) and mole fractions of detected products in the effluent gas streams of CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems, respectively, have been determined. The effects of four experimental parameters, input power, O{sub 2}/CHF{sub 3} or H{sub 2}/CHF{sub 3} ratio, operational pressure, and the CHF{sub 3} feeding concentration were investigated. The same species detected in the effluent gas streams of both CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems were CH{sub 2}F{sub 2}, CF{sub 4}, HF, and SiF{sub 4}. However, the CO{sub 2} and COF{sub 2} were detected only in the CHF{sub 3}/O{sub 2}/Ar plasma system and the CH{sub 4}, C{sub 2}H{sub 2}, and CH{sub 3}F were detected only in the CHF{sub 3}/H{sub 2}/Ar plasma system. The results of a model sensitivity analysis showed that the input power was the most influential parameter for {eta}CHF{sub 3} both in the CHF{sub 3}/O{sub 2}/Ar and CHF{sub 3}/H{sub 2}/Ar plasma systems. Furthermore, the possible reaction pathways were built up and elucidated in this study. The addition of hydrogen for CHF{sub 3} decomposition can produce a significant amount of HF and the main carbonaceous byproducts were CH{sub 4} and C{sub 2}H{sub 2}. Even though the {eta}CHF{sub 3} in the CHF{sub 3}/H{sub 2}/Ar plasma system is lower than that in the CHF{sub 3}/O{sub 2}/Ar plasma system, but due to the more advantages mentioned above, a hydrogen-based RF plasma system is a better alternative to decompose CHF{sub 3}.},
doi = {10.1021/ie9900519},
journal = {Industrial and Engineering Chemistry Research},
number = 9,
volume = 38,
place = {United States},
year = {1999},
month = {9}
}