Circular treating process of solid waste from vanillin synthesis

Abstract

The present invention relates to circular treating process of solid waste from guaiacol-nitroso process the synthesize vanillin. The circular treating process includes the following steps: adding copper sulfate into alcohol and heating reflux through stirring; adding p-amino-N, N-dimethyl aniline dissolved in alcohol, dropping sulfuric acid, and adding sodium nitrite to react until becoming stable; adding water to distill out alcohol, cooling with ice water, adding sodium hydroxide solution to become alkaline, and heating to distill until reaching distillate without oil drop; extracting the distillate with chloroform, taking the chloroform layer, adding magnesium sulfate, drying, filtering, and distilling out chloroform to obtain product N, N-dimethyl aniline. The present invention has low treating cost and no secondary pollution, and the product N, N-dimethyl aniline may be further used in preparing vanillin.

Description

technical field [0001] The invention relates to a recycling treatment method for industrial solid waste obtained when vanillin is synthesized by a guaiacol-nitroso method. Background technique [0002] There are many methods for producing and preparing vanillin, among which the guaiacol-nitroso method is widely used because of its easy availability of raw materials, low cost and simple operation. However, a big defect of adopting this method is exactly that a kind of solid by-product p-amino N, N dimethylaniline can be obtained in the production and preparation process, and this solid by-product is a kind of polluted larger solid waste, which is black shape, with a pungent odor. Its process route is as figure 1 As shown, N, N dimethylaniline obtains the key intermediate A after subdigestion and reduction, the key intermediate B is obtained after the reaction of guaiacol and formaldehyde, and the vanillin can be obtained after the reaction of A and B. But at the same time ...

AI Technical Summary

Problems solved by technology

[0003] Before the present invention, the method for processing p-amino N,N dimethylaniline was to remove the amino group under the action of hypophosphorous acid after diazotization, and it needed to be cooled to below 5°C before it could be recycled for production and preparation of pandan The raw material-N of prime, N dimethylaniline, but the cost of this method is far higher than N, the cost of N dimethylaniline itself, can't be applied in actual production, preparation, as figure 2 shown; secondly, it is to adopt the method of deep burial or incineration to deal with p-amino N, N dimethylaniline solid waste, but it will cause secondary pollution, and it has not been recycled. Under the constraints of laws and regulations to protect the environment, this is prohibited processing method

Images