Method of and system for processing halogenated hydrocarbons

• US 5,569,810 A
• Filed: 03/02/1995
• Issued: 10/29/1996
• Est. Priority Date: 03/18/1994
• Status: Expired due to Term

• Current Assignee: Samco International, Inc.
• Original Assignee: Samco International, Inc.
• Inventors: Tsuji, Osamu
• Primary Examiner(s): Gorgos, Kathryn
• Assistant Examiner(s): DELACROIX MUIRHEI, CYBILLE
• Application Number:
  US08/398,178
• Time in Patent Office: 607 Days
• Field of Search: 427/490, 588/212, 588/227, 204/157.15
• US Class Current: 588/311
• CPC Class Codes: B01D 2257/206 Organic halogen compounds
• CPC Class Codes: B01D 2259/818 Employing electrical discharges or the generation of a plasma
• CPC Class Codes: B01D 53/32 by electrical effects other than those provided for in group B01D61/00
• CPC Class Codes: B01D 53/70 Organic halogen compounds

Abstract

System for and a method of fixing chlorofluorocarbons or other halogenated hydrocarbons, for example, CHF₃ or CCl₂ F₂ recirculated and collected or discharged from a dry etching apparatus, so as to make the chlorofluorocarbon or halogenated hydrocarbon harmless against the earth'"'"'s ozone layer. A gaseous hydrocarbon like ethane, ethylene or acetylene gas is mixed with a chlorofluorocarbon or other halogenated hydrocarbon gas in a reaction tube 61. The mixed gas is then excited to a plasma state for plasma copolymerization. A solid copolymer of the halogenated hydrocarbon and the hydrocarbon generated by the plasma copolymerization is deposited and accumulated onto the inner wall of the reaction tube 61 or on a fixation member 14.

Claims

1. A method of processing a chlorofluorocarbon gas waste material comprising the steps of:

a. mixing a hydrocarbon gas with the chlorofluorocarbon gas waste material to create a mixed gas; and

b. exciting the mixed gas to a plasma state for plasma copolymerization, generating a copolymer of molecules of the chlorofluorocarbon gas waste material and the hydrocarbon gas, the copolymer being accumulated on a fixation member, wherein a majority of chlorofluorocarbons in said chlorofluorocarbon gas waste material is prevented by said method of processing from being atmospherically released.

2. The chlorofluorocarbon processing method according to claim 1, wherein the chlorofluorocarbon gas is CFC-113, and the hydrocarbon gas is a lower hydrocarbon gas containing three or less carbon atoms.

3. The chlorofluorocarbon processing method according to claim 1, wherein the chlorofluorocarbon gas is CFC-113, the hydrocarbon gas is ethane gas, and the molar mixture ratio is [CFC-113]:

[ethane]=50;

50-90;

10.

4. The chlorofluorocarbon processing method according to claim 1, wherein the chlorofluorocarbon gas is CFC-113, the hydrocarbon gas is ethylene gas, and the molar mixture ratio is [CFC-113]:

[ethylene]=25;

75-75;

25.

5. The chlorofluorocarbon processing method according to claim 1, wherein the chlorofluorocarbon gas is CFC-113, the hydrocarbon gas is acetylene gas, and the molar mixture ratio is [CFC-113]:

[acetylene]=15;

85-65;

35.

6. The method according to claim 1, wherein said chlorofluorocarbon gas waste material is discharged from a dry etching apparatus for the mixing with said hydrocarbon gas.

7. The method according to claim 1, wherein said chlorofluorocarbon gas waste material is discharged from a waste storage container for mixing with said hydrocarbon gas.