Method of cracking polymeric materials catalyzed by copper

• US 5,728,909 A
• Filed: 02/14/1994
• Issued: 03/17/1998
• Est. Priority Date: 12/30/1992
• Status: Expired due to Fees

• Current Assignee: Ohio University
• Original Assignee: Ohio University
• Inventors: Butcher, Jared A. Jr.
• Primary Examiner(s): Caldarola, Glenn
• Assistant Examiner(s): Wood, Elizabeth D.
• Application Number:
  US08/195,232
• Time in Patent Office: 1,492 Days
• Field of Search: 585/241, 585/700, 585/752
• US Class Current: 585/241
• CPC Class Codes: C07C 4/00 Preparation of hydrocarbons from hydrocarbons containing a larger number of carbon atoms redistribution reactions involving splitting C07C6/00; cracking hydrocarbon oils C10G
• CPC Class Codes: C07C 4/22 by depolymerisation to the original monomer, e.g. dicyclopentadiene to cyclopentadiene
• CPC Class Codes: C10G 1/10 from rubber or rubber waste

Abstract

The present invention is a method for depolymerizing or "cracking" polymeric materials. The method of the present invention may be used in the disposal and/or recycling of such materials. Products of the degradation of polymeric materials using the present method may be recycled or more easily treated for disposal. The present invention is a process for degrading, depolymerizing or "cracking" a polymeric material, otherwise amenable to cracking by alkali fusion, comprising the steps of:

(a) preparing a molten reaction mixture comprising:

(i) a basic material;

(ii) a source of copper; and

(iii) said polymeric material; and

(b) maintaining said molten mixture at a temperature sufficient to reflux said molten mixture for sufficient time to depolymerize said polymeric material.

Claims

1. A method of depolymerizing a polymeric material, said method comprising the steps:

(a) preparing a molten mixture comprising;

(i) a basic material capable of producing hydroxide ions;

(ii) a source of copper selected from the group consisting of copper metal, univalent copper, divalent copper, and mixtures thereof; and

(iii) said polymeric material selected from the group consisting of thermoplastic polymeric material, thermosetting polymeric material and mixtures thereof; and

(b) maintaining said molten mixture at a temperature sufficient to reflux said molten mixture so as to produce a vapor and at a temperature, as measured from said vapor, below about 250°

C. for sufficient time to depolymerize said polymeric material.

2. A method according to claim 1 wherein said basic material is selected from the group consisting of NaOH, KOH, Na₂ B₄ O₇ ·

10 H₂ O, Na₃ BO₃, Na₂ SiO₃, K₂ SiO₃, and mixtures thereof.

3. A method according to claim 2 wherein said basic material comprises NaOH and KOH.

4. A method according to claim 2 wherein said basic material comprises Na₂ B₄ O₇ 10H₂ O and NaOH.

6. A method according to claim 1 wherein said source of copper is copper metal.

7. A method according to claim 1 wherein said molten mixture is maintained in a reaction vessel comprising copper metal during step (b).

8. A method according to claim 1 wherein said source of copper is copper (I) oxide.

9. A method according to claim 1 wherein said polymeric material is thermoplastic polymeric material.

10. A method according to claim 1 wherein step (b) is carried out under air at atmospheric pressure.

11. A method according to claim 9 wherein said thermoplastic polymeric material is selected from the group consisting of polyethylene, polystyrene, polyvinylchloride, and polypropylene and mixtures thereof.

5. A method according to claim wherein said source of copper is present an mount sufficient to provide a concentration of cooper of at least 5% by weight of said molten mixture.