Process for extracting high-purity m-dichlorobenzene from solid waste chlorobenzene tar

Abstract

The invention discloses a process for extracting high-purity m-dichlorobenzene from solid waste chlorobenzene tar, which is a process for extracting the m-dichlorobenzene from a mixture of m-dichlorobenzene, o-dichlorobenzene and p-dichlorobenzene separated from the solid waste chlorobenzene tar by adopting indirect adsorption of zeolite. The process comprises the following steps of: preparing mixed solution of alkanes, then separating a mixture of p-dichlorobenzene and o-dichlorobenzene by using the adsorption of the zeolite, and finally obtaining the m-dichlorobenzene. The process has the advantages that: the process for extracting the m-dichlorobenzene from the isomer mixture is an extraction process implemented by adopting a physical method, and the product obtained by the process hashigh purity and high yield.

Description

technical field [0001] The invention relates to a process for extracting m-dichlorobenzene from a mixture of isomers, in particular to a process for extracting m-dichlorobenzene by using a physical method. The finished product obtained by the process has high purity and high yield. Background technique [0002] m-Dichlorobenzene is an important raw material for organic synthesis in fine chemical industries such as dyes, pigments, medicines, and pesticides. [0003] The solid waste chlorinated benzene tar contains low levels of chlorinated benzene, m-dichlorobenzene, p-dichlorobenzene, ortho-dichlorobenzene, as well as a small amount of water and other impurities, which is acidic and cannot be used directly. If it cannot be disposed of properly, it will cause serious environmental pollution. The use of incineration method not only consumes a lot of energy, but also produces a large amount of waste gas and produces carcinogens-dioxins; the use of industrial water treatment met...

AI Technical Summary

Problems solved by technology

[0003] The solid waste chlorinated benzene tar contains low levels of chlorinated benzene, m-dichlorobenzene, p-dichlorobenzene, ortho-dichlorobenzene, as well as a small amount of water and other impurities. It is acidic and cannot be used directly.

If it cannot be disposed of properly, it will cause serious environmental pollution. The use of incineration method not only consumes a lot of energy, but also produces a large amount of waste gas and produces carcinogens-dioxins; the use of industrial water treatment method requires a large amount of Manpower and material resources, the treatment results still cannot guarantee the emission standards

No matter which of the above methods is used to treat the solid waste chlorinated benzene tar, the available chlorinated benzene, p-dichlorobenzene, m-dichlorobenzene, and o-dichlorobenzene cannot be extracted, which is easy to form secondary pollution

From the analysis of public reports in domestic literature, no effective solutions have been found. At present, foreign companies are no longer building or expanding dichlorobenzene plants due to environmental pressure.