Monomer recovery from polymeric materials

Patent 5326919 Issued on July 5, 1994. Estimated Expiration Date:

February 8, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3901951

Method for thermal decomposition of plastic scraps and apparatus for disposal of plastic scraps
Patent #: 4584421
Issued on: 04/22/1986
Inventor: Saito , et al.

Monomeric recovery from polymeric materials Patent #: 5136117
Issued on: 08/04/1992
Inventor: Paisley, et al.

Inventors

Assignee

Battelle Memorial Institute

Application

No. 014833 filed on 02/08/1993

US Classes:

585/241, From synthetic resin or rubber585/648By C content reduction, e.g., cracking, etc.

Examiners

Primary: Pal, Asok
Assistant: Achutamurthy, P.

Attorney, Agent or Firm

Watkins, Dunbar & Pollick

Foreign Patent References

982078 CA. 02/12/2012
9105976 EP. 02/12/2012
2234755 DE. 02/12/2012
1398858 GB. 02/12/2012

International Class

C07C 004/22

Abstract

A method is described for the recovery of high yields of monomers from waste and scrape polymeric materials with minimal amounts of char and tar. The process involves heating the polymer at a heating rate of at least 500° C./sec in a flow-through reactor. Heating is accomplished by contacting the polymer with a heat transfer material such as hot incandescent sand. A flow-through reactor is used to provide the high heating rates and short reactor residence times for the monomer product. The flow through reactor may be a circulating fluidized bed reactor, an entrainment reactor, a cyclonic reactor or a gravity reactor.

Other References

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