Processes for preparing 2,5-dichlorophenol
AssigneeMonsanto Technology LLC
InventorsJohn H. Ahn, Don Probst, Kam-To Wan, John Wang
Life of this patent
Estimating the term…
Abstract
Processes for producing 2,5-dichlorophenol and 3,6-dichloro-2-methoxybenzoic acid are described. Various processes for isomerizing 2,4-dichlorophenol over a zeolite catalyst to form 2,5-dichlorophenol are provided. Processes for preparing 2,5-dichlorophenol including hydroxylating 1,4-dichlorobenzene are also described. The present invention also relates to processes for producing 3,6-dichloro-2-methoxybenzoic acid.
Claims23
A process for producing 2,5-dichlorophenol, the process comprising:
- contacting a feed comprising 2,4-dichlorophenol with a zeolite catalyst in acid form in an isomerization zone to isomerize at least a portion of the 2,4-dichlorophenol to 2,5-dichlorophenol, wherein the zeolite catalyst has a SiO2/Al2O3 mole ratio of no greater than about 35:1.
A process for producing 2,5-dichlorophenol, the process comprising:
- contacting a feed comprising 2,4-dichlorophenol and 3,4-dichlorophenol with a zeolite catalyst in acid form in an isomerization zone to isomerize at least a portion of the 2,4-dichlorophenol to 2,5-dichlorophenol.
A process for producing 2,5-dichlorophenol, the process comprising:
- contacting a feed comprising 2,4-dichlorophenol with a zeolite catalyst in acid form in an isomerization zone to isomerize at least a portion of the 2,4-dichlorophenol to 2,5-dichlorophenol;
- suspending contact of the feed comprising 2,4-dichlorophenol with the zeolite catalyst;
- and
- contacting the zeolite catalyst with steam at a temperature from about 250° C. to about 375° C. to rejuvenate the catalyst.
Dependencies are inferred from the claim text.