Environment-friendly treatment method of hexachlorobenzene

Abstract

The invention discloses an environment-friendly treatment method of hexachlorobenzene. The method comprises the following steps: (1) putting hexachlorobenzene and an active potassium fluoride solution organic solvent into a single reactor; (2) performing pressure test leakage detection and nitrogen replacement on the single reactor containing a reaction solution; (3) heating the single reactor to 200-300 DEG C, boosting the pressure to 2.0-3.0MPa, and reacting for 10-15h at a reaction temperature and a reaction pressure; (4) distilling off reactants in the single reactor, condensing and then collecting the reactants; (5) performing distillation separation on hexachlorobenzene and chloropentafluorobenzene in the reactants; and (6) performing reduced pressure distillation to collect fluorochlorobenzene (byproduct) and the organic solvent in the single reactor, taking out potassium chloride residues in the single reactor, drying fluorochlorobenzene, and then adding fluorochlorobenzene into the single reactor for continuous use. The method disclosed by the invention is mild in reaction condition and relatively high in conversion rate and yield, and a practical chemical intermediate is obtained while pollution is reduced, so that the method has a broad application prospect.

Description

technical field [0001] The invention relates to a comprehensive utilization method of chemical by-products, in particular to an environmentally friendly treatment method for hexachlorobenzene. Background technique [0002] Hexachlorobenzene is one of the first batch of 12 controlled chemical substances in 3 categories announced by the United Nations Environment Program "Stockholm Convention on Persistent Organic Pollutants (PoPs), and the hazards to human health and environmental pollution are imminent. Hexachlorobenzene has a completely symmetrical structure, and has many chlorine substitutions, high toxicity, and very difficult to degrade. According to the survey, at least 600 tons of hexachlorobenzene are produced in the domestic chemical production process every year, and the sealed hexachlorobenzene waste has the risk of leakage and diffusion, which poses a huge hidden danger to the safety of the surrounding ecological environment. Hexachlorobenzene is usually disposed...

AI Technical Summary

Problems solved by technology

Hexachlorobenzene has a completely symmetrical structure, and has a large number of chlorine substitutions, high toxicity, and very difficult to degrade

According to the survey, at least 600 tons of hexachlorobenzene are produced in the domestic chemical production process every year, and the sealed hexachlorobenzene waste has the risk of leakage and diffusion, which poses a huge hidden danger to the safety of the surrounding ecological environment

Hexachlorobenzene is usually disposed of by simple incineration, which may produce dioxins during the incineration process, causing great harm to the environment

[0014] This method has a short process route and low cost of raw materials, but it also has low yield and serious coking in the reactor, which limits the industrial application

[0015] In summary, the existing synthetic methods of hexafluorobenzene and chloropentafluorobenzene have the disadvantages of low conversion rate, low yield, serious coking in the reactor, and being unfavorable for industrialized production