Method for preparing pentachloropyridine by utilizing DCTF rectifying short steaming residues
US10017473B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Jan 12, 2017 |
| Grant date | Jul 10, 2018 |
| Priority date | — |
| Expiry date | Jan 12, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D213/61
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method for preparing pentachloropyridine by utilizing DCTF rectifying short steaming residues, comprising the following steps: converting polymers in the residues through in situ catalytic cracking and vacuum distillation by using the catalytic degradation function of a catalyst formed by aluminum oxide, silicon oxide, zirconia, 4A zeolite, magnesium oxide, mordenite and HZSM-5 zeolite on the polymers in the DCTF rectifying short steaming residues into small molecular compounds and obtaining pentachloropyridine-containing crude oil; washing the pentachloropyridine-containing crude oil by using an aqueous solution of an alkaline assistant formed by sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate and sodium hydroxide, carrying out reduced pressure rectification, refrigerating crystallization, vacuum filtration or centrifuging separation, solvent washing, and vacuum drying method sequentially to obtain a pentachloropyridine product with a mass percentage content greater than 95% at a yield being 1-15% of the mass of the DCTF rectifying short steaming residues.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.