Supercritical carbon dioxide morphologically modified acid-based halloysite catalyst
US9982092B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2017 |
| Grant date | May 29, 2018 |
| Priority date | — |
| Expiry date | Apr 4, 2037 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/54
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The efficient production of poly(tetramethylene ether) diacetate [PTMEA] or other diesters, from tetrahydrofuran [THF] is obtained utilizing an acid-based catalyst that is based on a morphologically reconfigured and Bronsted acidity enhanced halloysite derived from a preparation method of using naturally occurring halloysites. More specifically, the method relates to morphological modification of the internal pore structure of halloysites via supercritical carbon dioxide treatment directly applied onto the raw halloysite minerals, that yields highly synergistic and reproducible results of elimination of inaccessible and detrimental extra-small pores. PTMEA is readily converted to poly(tetramethylene ether) glycol (PTMEG) by a transesterification reaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.