Abstract
Technological aspects of the synthesis of 2,4-dichlorophenol The main factors influencing the selectivity of chlorophenols synthesis were described. The loss of raw materials and the composition of wastes obtained in a conventional technology of 2,4-D production based on 2,4-dichlorophenol (2,4-DCP) of the 89% purity were presented. The influence of some homogenous catalysts on the selectivity of 2,4-dichlorophenol obtained in phenol and chlorine reaction was examined. Using the combined catalyst enables to chlorinate selectively the monochlorophenols to 2,4-DCP without an undesirable increasing of the 2,6-dichlorophenol and 2,4,6-trichlorophenol contents. The catalyst transformations during the reaction of phenol chlorination were investigated and the method of its elimination after the reaction was elaborated.
Highlights
2,4,6-trichlorophenol (2,4,6-TCP), belongs to the group of „light chlorophenols”
During the GC analysis of 2,4-dichlorophenol obtained by phenol chlorination with the addition of diphenyl sulfide (DPS), it can be observed that some signals of a few substances having retention time longer than chlorophenols appear
The organic and inorganic catalysts are successfully removed from technical 2,4-DCP with the aid of washing out with hydrochloric acid and the sorption on mineral sorbents. 2,4-DCP obtained by phenol chlorination contains trace amounts of PCDD/F contaminants allowed in the standards of technical products
Summary
2,4-Dichlorophenol (2,4-DCP), with p- and omonochlorophenols, 2,6-dichlorophenol (2,6-DCP) and. Moszczyñski, Bia3ek and others patented the synthesis of 2,4-DCP of high purity 95% with the use of a catalytic complex, which contains Lewis acid and bivalent sulfur compounds[22] Another problem appearing in the production of 2,4dichlorophenol are trace contaminants of high toxicity. A lot of reducing agents, which are acceptors of chlorine, are mentioned in the patent, for example organic phosphorites, organic sulfides, metal hydrides, metals, phenols, chlorophenols, alkylphenols and dihydroxynaphtalenes Such reductants stabilize the mixture obtained during phenols and chlorophenols chlorination in such a way that gem-dichloro unsaturated cyclic ketones are converted into chlorophenols or they react with cyclic ketones, giving heavy compounds such as biphenyls and phenoxyphenols as products.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
