Chemistry of inorganic compounds – Modifying or removing component of normally gaseous mixture – Halogenous component
Patent
1996-10-29
1998-10-06
Straub, Gary P.
Chemistry of inorganic compounds
Modifying or removing component of normally gaseous mixture
Halogenous component
423219, 588206, 588248, B01D 5368, B01D 5370
Patent
active
058172840
ABSTRACT:
The present invention relates to a method for decomposing any of chlorocarbons, chlorofluorocarbons, perfluorocarbons and SF.sub.6 contained in a gas. This method includes the step of bringing the gas into contact, at a temperature of at least 300.degree. C., with a first mixture consisting essentially of 0.05-40 wt % of potassium hydroxide and at least one compound selected from the group consisting of alkali-earth-metal oxides and alkali-earth-metal hydroxides, for decomposing the at least one halide compound. When the halide compound-containing gas further contains oxygen, this gas may be brought into contact, at a temperature of at least 500.degree. C., with at least one first substance selected from the group consisting of active carbon, iron powder and nickel powder, for removing the oxygen from the gas, prior to the halide compound decomposition. When the halide compound-containing gas still further contains a strong oxidizing gas (e.g., fluorine), this gas may be brought into contact, at a temperature of at least 300.degree. C., with at least one second substance selected from the group consisting of Si, Ti, Ge, W, Mo, Fe, Mn, Co, Zn, Sn, B, Zr and compounds of these elements, except oxides of these elements, such that the oxidizing gas turns into a compound that is not reactive with the at least one first substance. According to this method, it is possible to decompose halide compounds contained within a gas, using a smaller equipment, at a lower temperature, as compared with conventional methods.
REFERENCES:
patent: 1490546 (1924-04-01), Thorssell et al.
patent: 3699209 (1972-10-01), Ward
patent: 4654203 (1987-03-01), Maurer et al.
patent: 5416247 (1995-05-01), Webster
Database WPI, Section Ch, Week 9644, Derwent Publications Ltd. London, GB; Class E37, AN 96-437524, XP002024980 for JP-A-08 215 538 (Central Glass Co., Ltd.), Aug. 27, 1996 (abst.).
Patent Abstracts of Japan, vol. 011, No. 038 (C-401), Feb. 4, 1987 for JP-A-61 204025 (Central Glass Co., Ltd.), Sep. 10, 1986.
Mizuno, "About Decomposition of Fluorine", Bosei Kanri (Rustproof Management), No. 11, pp. 7-13 (1992) no month.
Urano, "Decomposition of Chlorofluorocarbons", Kagaku Sosetsu (Chemistry Review), No. 11, pp. 144-158 (1991) no month.
Fukunaga et al., "Reactivity of Activated Carbon to Which Exhaust Gas of Semiconductor Production Has Adsorbed", 25th Anzen Kogaku Kenkyu Happyoukai Koen Yokoshu (Papers presented in 25th Meeting of Safety Engineering), pp. 19-22 (1992) no month.
Johnson et al. "A Closed-Cycle Gas Recirculating . . . " Appl. Phys. Lett. 32(5) pp. 291-292, Mar. 1978.
Matsuoka Nobuhiko
Nakagawa Shinsuke
Nakano Hisaji
Ueda Tetsuo
Central Glass Company Limited
Straub Gary P.
Vanoy Timothy C.
LandOfFree
Method for decomposing halide-containing gas does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for decomposing halide-containing gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for decomposing halide-containing gas will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-74250