US4351978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the disposal of polychlorinated biphenyls
Assignee: Osaka Prefectural Government
•
Filing: 1980-07-21
•
Granted: 1982-09-28
•
Expires: 2000-07-21
Abstract
Abstract The invention provides a method of disposing of polychlorinated biphenyls without causing a health hazard to the public in which the polychlorinated biphenyls are converted into harmless and useful compounds. This is accomplished by the hydrogenation-dechlorination thereof.
Inventors
- 👤 Yasuhiro Hatano
- 👤 Kazumune Nakao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:29
CPC Classifications
A; A62; A62D; A62D3/00; A62D3/30; A62D3/37; A62D2101/00; A62D2101/20; A62D2101/22; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/908; Y10S210/909
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
171 words
A method of treating polychlorinated biphenyl compounds in aqueous solution to render them substantially harmless, said method comprising: (A) admixing with said polychlorinated biphenyl compounds the following ingredients with respect to each one gram of chlorine atoms contained in said polychlorinated biphenyl compounds; (a) from 400 to 2000 ml of water; (b) from 0.5 to 1.25 gram equivalent weight of an alkali material selected from those metal hydroxides capable of reacting with hydrogen chloride to form a salt; (c) from 100 to 450 ml of an emulsifying-dispersing agent selected from the group consisting of low molecular weight alcohols; (d) a hydrogenation catalyst in an effective amount to promote the reaction between hydrogen and said polychlorinated biphenyl compounds; (B) maintaining said admixture within a pressure range of normal to 100 atmospheres and within a temperature range not higher than 200° C. and, while it is so maintained, introducing gaseous hydrogen in an amount greater than that calculated to be necessary to react with all the chlorines present in the polychlorinated biphenyl compounds.
Claim 2
Independent Claim
171 words
A method of treating polychlorinated biphenyl compounds in aqueous solution to render them substantially harmless, said method comprising: (A) admixing with said polychlorinated biphenyl compounds the following ingredients with respect to each one gram of chlorine atoms contained in said polychlorinated biphenyl compounds; (a) from 400 to 2000 ml of water; (b) from 0.5 to 1.25 gram equivalent weight of an alkali material selected from those metal hydroxides capable of reacting with hydrogen chloride to form a salt; (c) from 100 to 450 ml of an emulsifying-dispersing agent selected from the group consisting of low molecular weight alcohols; (d) a hydrogenation catalyst in an effective amount to promote the reaction between hydrogen and said polychlorinated biphenyl compounds; (B) maintaining said admixture within a pressure range of normal to 100 atmospheres and within a temperature range not higher than 200° C. and, while it is so maintained, introducing gaseous hydrogen in an amount greater than that calculated to be necessary to react with all the chlorines present in the polychlorinated biphenyl compounds.
Claim 3
Dependent Claim
57 words
A method of disposing of polychlorinated biphenyls as claimed in claim 1, wherein the amount of said water ranges from 900 ml to 1200 ml, the alkali from 0.75 to 1.1 gram equivalent weight, and the alcohol from 170 ml to 380 ml, with respect to chlorine of 1.0 gram equivalent weight contained in said polychlorinated biphenyls.
Claim 4
Dependent Claim
33 words
A method as claimed in claim 1 in which said treatment of polychlorinated biphenyl compounds is performed at a temperature not higher than 200° C. under a pressure of normal to 100 atm.
Claim 5
Dependent Claim
32 words
A method as claimed in claim 1 in which said treatment of polychlorinated biphenyl compounds is performed at a temperature of 40° to 160° under a pressure of normal to 30 atm.
Claim 6
Dependent Claim
15 words
A method as claimed in claim 1 in which said alkali material is sodium hydroxide.
Claim 7
Dependent Claim
15 words
A method as claimed in claim 1 in which said alkali material is potassium hydroxide.
Claim 8
Dependent Claim
15 words
A method as claimed in claim 1 in which said emulsifying-dispersing agent is methyl alcohol.
Claim 9
Dependent Claim
15 words
A method as claimed in claim 1 in which said emulsifying-dispersing agent is ethyl alcohol.
Claim 10
Dependent Claim
15 words
A method as claimed in claim 1 in which said emulsifying-dispersing agent is isopropyl alcohol.
Claim 11
Dependent Claim
17 words
A method as claimed in claim 1 in which said hydrogenation catalyst is a Raney nickel catalyst.
Claim 12
Dependent Claim
17 words
A method as claimed in claim 1 in which said hydrogenation catalyst is a carbon-supported palladium catalyst.
Claim 13
Independent Claim
141 words
A method of treating polychlorinated biphenyl compounds in aqueous solution to render them substantially harmless, said method comprising: (A) admixing in an aqueous medium (a) said polychlorinated biphenyl compounds to be treated; (b) an emulsifying-dispersing agent which is a low molecular weight alcohol and which is effective to and present in sufficient amount to emulsify and disperse said polychlorinated biphenyl compounds; (c) strongly basic alkali material capable of reacting with hydrogen chloride to form a salt, said alkali material being present in sufficient amount to react with all hydrogen chloride formed; (d) a hydrogenation catalyst in an amount effective to promote the reaction between hydrogen and said polychlorinated biphenyl compounds; (B) introducing gaseous hydrogen to said admixture, hydrogen being introduced in a greater amount than the calculated amount necessary to react with all the chlorines present in the polychlorinated biphenyl compounds.
Claim 14
Independent Claim
141 words
A method of treating polychlorinated biphenyl compounds in aqueous solution to render them substantially harmless, said method comprising: (A) admixing in an aqueous medium (a) said polychlorinated biphenyl compounds to be treated; (b) an emulsifying-dispersing agent which is a low molecular weight alcohol and which is effective to and present in sufficient amount to emulsify and disperse said polychlorinated biphenyl compounds; (c) strongly basic alkali material capable of reacting with hydrogen chloride to form a salt, said alkali material being present in sufficient amount to react with all hydrogen chloride formed; (d) a hydrogenation catalyst in an amount effective to promote the reaction between hydrogen and said polychlorinated biphenyl compounds; (B) introducing gaseous hydrogen to said admixture, hydrogen being introduced in a greater amount than the calculated amount necessary to react with all the chlorines present in the polychlorinated biphenyl compounds.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-27 | 1986-03-29 | 1986-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-27 | 1990-03-29 | 1990-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-27 | 1994-03-29 | 1994-09-28 | $7700.00 | Window Closed / Lapsed |