Patent US3901951A successfully refreshed from Google Patents.
US3901951A
Expired / Lapsed
US
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Method for treating waste plastics
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1973-03-26
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Granted: 1975-08-26
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Expires: 1993-03-26
Abstract
Abstract A method for treating waste plastics characterized by melting waste of plastics derived from at least one monomer selected from aliphatic and aromatic unsaturated hydrocarbons, bringing the melt into contact with a particulate solid heat medium in fluidized state maintained at a temperature of 350*-550*C to effect pyrolysis of the melt, and thereafter collecting and condensing the resulting gaseous product to recover a mixture of liquid hydrocarbons. Such mixture of liquid hydrocarbons contains ethylenically unsaturated compounds useful as starting material for the production of plastics, such as various olefins and styrene.
Inventors
- 👤 Hiroki Nishizaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:39
CPC Classifications
C; C10; C10B; C10B49/00; C10B49/02; C10B49/04; C10B49/08; C10B49/10; C07; C07C; C07C4/00; C07C4/02; C07C4/04; C07C4/22; C10B49/16; C10B49/20; C10B49/22; C10B53/00; C10B53/07; C10G; C10G1/00; C10G1/02; Y; Y02; Y02P; Y02P20/00; Y02P20/141; Y02P20/143; Y10; Y10S; Y10S585/00; Y10S585/919; Y10S585/921; Y10S585/924; Y10S585/925
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
70 words
A METHOD FOR RECOVERING USEFUL COMPONENTS FROM WASTE PLASTIC DERIVED FROM AT LEAST ONE MONOMER SELECTED FROM ALIPHATIC AND AROMATIC UNSATURATED HYDROCARBONS, CHARACTERIZED BY MELTING THE WASTE PLASTIC, BRINGING THE MELT INTO CONTACT WITH A PARTICULATE SOLID HEAT MEDIUM IN FLUIDIZED STATE MAINTAINED AT A TEMPERATURE OF 350*-550*C TO EFFECT PYROLYSIS OF THE MELT, AND THEREAFTER COLLECTING AND CONDENSING THE RESULTANT GASEOUS PRODUCT TO RECOVER A MIXTURE OF LIQUID HYDROCARBONS.
Claim 2
Independent Claim
70 words
A METHOD FOR RECOVERING USEFUL COMPONENTS FROM WASTE PLASTIC DERIVED FROM AT LEAST ONE MONOMER SELECTED FROM ALIPHATIC AND AROMATIC UNSATURATED HYDROCARBONS, CHARACTERIZED BY MELTING THE WASTE PLASTIC, BRINGING THE MELT INTO CONTACT WITH A PARTICULATE SOLID HEAT MEDIUM IN FLUIDIZED STATE MAINTAINED AT A TEMPERATURE OF 350*-550*C TO EFFECT PYROLYSIS OF THE MELT, AND THEREAFTER COLLECTING AND CONDENSING THE RESULTANT GASEOUS PRODUCT TO RECOVER A MIXTURE OF LIQUID HYDROCARBONS.
Claim 3
Dependent Claim
16 words
A method according to claim 1 wherein sand is used as the particulate solid heat medium.
Claim 4
Dependent Claim
17 words
A method according to claim 1 wherein air is used for fluidizing the particulate solid heat medium.
Claim 5
Dependent Claim
22 words
A method according to claim 3 wherein the amount of air for fluidization is about 0.3-0.7 Kl per Kg of waste plastic.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |