Method for treating wastewater with benzoic acid

Abstract

The invention discloses a method for treating wastewater with benzoic acid and belongs to the technical field of water treatment. The method comprises the following steps: firstly, adding an iron ion additive into wastewater with benzoic acid, adjusting the pH value to be weak acidity by using chemicals, further adding activated carbon, performing filtering separation so as to obtain a filtered liquid of which the content of the benzoic acid is reduced, and introducing a transition liquid into a later water treatment system for treatment. As the iron ion additive is adopted to complex the benzoic acid, and the activated carbon is added for filtering separation, the content of the benzoic acid in the wastewater is remarkably reduced, the treatment burden of the later water treatment system is alleviated, the treatment cost is lowered, and the environment can be protected.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and in particular relates to a method for treating wastewater containing benzoic acid. Background technique [0002] The wastewater containing benzoic acid mentioned above mainly refers to, but is not limited to, the wastewater generated in the process of preparing organic peroxides or other chemical products from benzoyl chloride. Along with the development of industry, more and more manufacturers prepare the aforementioned organic peroxides and other chemicals by benzoyl chloride, and the waste water containing benzoic acid produced thereupon also increases accordingly, for example in the production of dibenzoyl peroxide ( In the process of BPO (hereinafter referred to as BPO), a small amount of benzoic acid is contained in the washing water produced by washing the crude BPO after the crude product of BPO is synthesized; The pH of the alkali washing water obtained after washing is adju...

AI Technical Summary

Problems solved by technology

The mother liquor obtained by this method contains a small amount of benzoic acid, and the residual benzoic acid will enter the sodium chloride, affecting the purity of sodium chloride.

[0004] Since benzoic acid has a certain solubility in water, the residual benzoic acid cannot be effectively removed by acidification

In addition, because the chemical structure of benzoic acid is relatively stable, it is often difficult to treat it by biodegradation methods. If the wastewater containing benzoic acid is directly introduced into the wastewater treatment system, the COD in the wastewater will increase after entering the wastewater treatment system. No small burden on the processing system

And if the wastewater containing benzoic acid enters the sodium chloride evaporation system, the residual benzoic acid will affect the purity of sodium chloride

[0005] As can be seen from the above, how to effectively reduce the content of benzoic acid in the waste water containing benzoic acid so as to reduce the pressure (or burden) of subsequent water treatment has become a technical problem that has plagued the industry and is expected to be solved. No related reports have been found in the patents and non-patent literature disclosed so far, and the technical solutions to be introduced below are produced under this background