Sequential pyrolysis of plastic to recover polystyrene HCL and terephthalic acid
US5464602A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1995 |
| Grant date | Nov 7, 1995 |
| Priority date | — |
| Expiry date | Jan 9, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G1/10
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process of pyrolyzing plastic waste feed streams containing polyvinyl chloride, polyethylene terephthalate, polystyrene and polyethylene to recover polystyrene HCl and terephthalic acid comprising: heating the plastic waste feed stream to a first temperature; adding an acid or base catalyst on an oxide or carbonate support; heating the plastic waste feed stream to pyrolyze polyethylene terephthalate and polyvinyl chloride; separating terephthalic acid or HCl; heating to a second temperature to pyrolyze polystyrene; separating styrene; heating the waste feed stream to a third temperature to pyrolyze polyethylene; and separating hydrocarbons.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.