New technology of producing trichloroaldehyde from chlorine oil

Abstract

A process for preparing trichloroacetaldehyde from alcohol or acetaldehyde includes such steps as reaction on Cl to generate chlorine oil, deacidifying or not, distilling or rectifying to obtain heavy component, medium-boiling compound and low-boiling compound, rejecting the heavy component, returning low-boiling component back to chlorinating system, and dewatering the medium-boiling compound (refined chlorine oil) to obtain target product.

Description

1. Technical field [0001] The present invention relates to a new production process of producing aldehyde hydrate from chlorine oil produced by chlorine gas and chlorine reaction with alcohol or acetaldehyde as raw material, and then using organic or inorganic dehydrating agent to produce chloral . 2. Background technology [0002] The background of the present invention is after alcohol or acetaldehyde and chlorine reaction generate chlorine oil, the way of traditional production chloral is to carry out dehydration with concentrated sulfuric acid, stay a large amount of so-called black acid after steaming out chloral, In fact, it is a mixture of a large amount of complex lipid compounds and dilute sulfuric acid. Due to the harmful substances such as trichloroacetaldehyde and trichloroacetic acid, the post-treatment of this acid is not only very annoying but also wastes a lot of resources. Unknown esters It also seriously pollutes the environment. Almost from the day when c...

AI Technical Summary

Problems solved by technology

[0002] The background of the present invention is after alcohol or acetaldehyde and chlorine reaction generate chlorine oil, the way of traditional production chloral is to carry out dehydration with concentrated sulfuric acid, stay a large amount of so-called black acid after steaming out chloral, In fact, it is a mixture of a large amount of complex lipid compounds and dilute sulfuric acid. Due to the harmful substances such as trichloroacetaldehyde and trichloroacetic acid, the post-treatment of this acid is not only very annoying but also wastes a lot of resources. Unknown esters It also seriously pollutes the environment. Almost from the day when chloral uses alcohol or acetaldehyde as the chlorination raw material and begins to use concentrated sulfuric acid as a dehydrating agent, the black acid nightmare is intertwined with chloral until the present invention appears. All efforts have failed to overcome the problems caused by black acid. In the original sulfuric acid dehydration process, there is still a large distillation loss during the distillation process, resulting in waste of alcohol

Chloral was originally a product with great potential for development, but it could not give full play to its potential because of black acid troubles. For example, chloral can be made into bisphenol C to produce polycarbonate, epoxy resin Esters, they are all bulk products, and it is impossible to develop bisphenol C without fundamentally solving the big pollution source of black acid; the production of chloroform and dimethylformamide from chlorine oil is relatively high because of the untreated chlorine oil; It is difficult to produce products with a purity greater than 95% in the dehydration process, and the product with a purity greater than 95% can be easily obtained by using this process; at present, the alcohol consumption in the process of producing chloral from chlorine oil is almost double the theoretical value Half, one of the important reasons is that the alcohol in the alcoholic aldehydes in chlorine oil is not recovered. Due to the existence of alcohol and alcoholic alcoholic aldehydes, the acid quickly turns black in the original sulfuric acid treatment process, and this part of the alcohol accounts for about the total loss. two thirds