Views:1 Author:Site Editor Publish Time: 2021-12-10 Origin:Site
N, N-dimethylformamide (DMF) is an organic solvent with stable chemical properties, high boiling point and excellent performance. In addition to halogenated hydrocarbons, it can be intersoluble with water and most organic solvents at any ratio. Because of its good solubility, it is known as "universal solvent".
DMF is also an important pesticide pharmaceutical intermediates, a variety of gas absorbent. There is a large amount of DMF in the wastewater discharged from the production process of chemical products. Every year, only the leather industry discharged about 100 million tons of wastewater containing DMF
DMF can damage human health through breathing and skin contact, irritate and damage eyes, and long-term exposure or inhalation will hinder hematopoietic function and cause liver disorders. And in the water will lead to the increase of BOD and nitrogen content, so that the water quality deteriorates rapidly, and is very difficult to biodegrade. The institute of Hygiene, Chinese Medical College pointed out that the recommended maximum allowable concentration of DMF in domestic surface water was 25 mg/L
Therefore, it is very necessary to treat wastewater containing DMF.
At present, the main treatment methods of wastewater containing DMF at home and abroad include biological method, physical and chemical method (adsorption, extraction), chemical method (catalytic oxidation, supercritical water oxidation, alkaline hydrolysis). Biological treatment of DMF wastewater has the disadvantages of long treatment time and incomplete degradation. DMF will cause microbial poisoning and cause a great impact on biological treatment. In physicochemical method, adsorption method has poor reproducibility and the possibility of secondary pollution of organic matter used in extraction. Chemical treatment of DMF wastewater has the advantages of quick reaction and simple operation. Compared with oxidation, alkaline hydrolysis treatment of DMF wastewater has the advantages of mild reaction conditions and thorough decomposition, and is more suitable for industrial application under the action of alkali. DMF hydrolysis reaction equation is as follows:
The wastewater containing DMF was added with NaOH to generate DMA and formate through alkaline hydrolysis. The DMA was driven out with air and collected.