Catalytic Depolymerisation of Polymeric Materials

• US 20180282648A1
• Filed: 06/05/2018
• Published: 10/04/2018
• Est. Priority Date: 01/17/2013
• Status: Active Grant

• Current Assignee: Greenmantra Recycling Technologies Ltd.
• Original Assignee: Greenmantra Recycling Technologies Ltd.
• Inventors: Kumar, Anil, Kumar, Pushkar
• Granted Patent: US 10,457,886 B2
• Time in Patent Office: Days
• CPC Class Codes: C08F 10/00 Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• CPC Class Codes: C08F 10/02 Ethene
• CPC Class Codes: C08F 110/06 Propene
• CPC Class Codes: C08F 8/50 Partial depolymerisation
• CPC Class Codes: C08J 11/10 by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation depolymerisation to the original monomer C07
• CPC Class Codes: C08J 2323/06 Polyethene
• CPC Class Codes: C10G 1/10 from rubber or rubber waste
• CPC Class Codes: C10M 107/02 Hydrocarbon polymers; Hydrocarbon polymers modified by oxidation
• CPC Class Codes: C10M 175/0025 by thermal processes
• CPC Class Codes: C10M 177/00 Special methods of preparation of lubricating compositions; Chemical modification by after-treatment of components or of the whole of a lubricating composition, not covered by other classes
• CPC Class Codes: C10M 2205/0225 used as base material
• CPC Class Codes: C10M 2205/0245 used as base material
• CPC Class Codes: C10M 2205/14 Synthetic waxes, e.g. polythene waxes
• CPC Class Codes: C10M 2207/126 monocarboxylic
• CPC Class Codes: C10N 2020/02 Viscosity; Viscosity index
• CPC Class Codes: C10N 2050/10 Semi-solids; greasy
• CPC Class Codes: Y02W 30/62 Plastics recycling; Rubber recycling

Abstract

A process for converting a molten polymeric material is provided. The process includes effecting disposition of a molten polymeric material, having at least one carbon-carbon double bond, in sufficient proximity to a catalyst material within a reaction zone, to affect a reactive process that effects generation of a reaction product. The reactive process effects cleaving of at least one carbon-carbon double bond. The catalyst material includes [Fe—Cu—Mo—P]/Al₂O₃ prepared by binding a ferrous-copper complex to an alumina support to generate an intermediate material and reacting the intermediate material with a heteropolyacid.

Claims

1. A process for depolymerizing polystyrene comprising disposing molten polystyrene in sufficient proximity to a catalyst material within a reaction zone to induce a reactive process that effects generation of a reaction product.

2. The process of claim 1, wherein said catalyst material comprises [Fe—

Cu—

Mo—

P]/Al₂O₃.

3. The process of claim 2, wherein said [Fe—

Cu—

Mo—

P]/Al₂O₃ is prepared by binding a ferrous-copper complex to an alumina support to generate an intermediate material and reacting the intermediate material with a Mo- and P-containing heteropolyacid.

4. The process of claim 1, wherein said molten polymeric material further comprises at least one second polymeric material, wherein said second polymeric material is selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, ethylene-vinyl acetate, polyphenylene ether, polyvinyl chloride, lignin, nylon, cellulose, and mixtures thereof.

5. The process of claim 4, wherein said at least one second polymeric material comprises polyethylene.

6. The process of claim 4, wherein said at least one second polymeric material comprises polypropylene.

7. The process of claim 4, wherein said at least one second polymeric material comprises waste polymeric material.

8. The process of claim 1, wherein said reactive process is conducted at a temperature between 300°

C. to 600°

C.

9. The process of claim 1, wherein said reactive process is conducted at a pressure between 50 psig to 350 psig.

10. The process of claim 1, wherein said reaction zone is a high-pressure reactor.

11. The process of claim 10, wherein said high-pressure reactor comprises at least one heater.

12. The process of claim 11, wherein a temperature is maintained using said at least one heater of said high-pressure reactor;

and said at least one heater is turned off and said reactive process is stopped when a pressure of said high-pressure reactor reaches a predetermined pressure value.

13. The process of claim 1, wherein said reaction product is a wax or grease base stock.

14. The process of claim 13, further comprising draining the converted wax or grease base stock into a container when said wax or grease base stock is liquid and is at a temperature above the flash point of said wax or grease base stock, respectively

15. The process of claim 13, wherein said reactive process is conducted at a variable pressure to produce different grades of said wax and grease base stock.

16. The process of claim 1, wherein said polystyrene is made molten by a heated extruder. The process of claim 16, wherein said extruder is in fluid communication with said reaction zone for feeding said molten polystyrene to said reaction zone.