SU62866A1 - Chlorination of acetone - Google Patents

Description

The Fritsch method is currently used to produce chloroacetone. According to this method, pieces of marble are swept into acetone and chlorine is passed in, adding water at the same time. A reaction occurs in the mixture:

СНзСОСНз + С1о + СНзСОСНоС + НС1 2НС1 + СаСОз CaClo + NaO + СОА

The addition of marble serves to bind hydrochloric acid, which causes side reactions during accumulation. At the end of chlorination, the layer of acetone-chloradeton mixture is separated from the aqueous layer of calcium chloride, and the mixture is subjected to fractional distillation. Fritsch's method, discontinuous and unequal in its course, is not convenient for production. In contrast to this method, the main essence of the proposed method is that acetone is washed with a concentrated calcium chloride solution during chlorination, which extracts hydrochloric acid, which is then neutralized in a separate vessel. This method is not difficult to implement as continuous, for example according to the scheme shown in the drawing.

The column}, which has scrubs for cooling water filled with chlorinated liquid, receives chlorine through tube 2, and acetone is poured from tank 3. From the tank 4, a 30-35% calcium chloride solution is fed in thin streams, which, after flowing through a layer of acetonacetone, extracts hydrochloric acid from it. The chloroacetone layer, as it is chlorinated, is discharged into receiver 5, from where it is sent to a continuous reflux column. The residual acidity of the chloro acetopic mixture should be kept at a level of 0.2-0.5 m; Before receiver 5, it is advisable to include another column for the final washing of the mixture with calcium chloride solution. The calcium chloride solution is collected in receiver 6 where it is neutralized with marble or lime; the neutralized solution is returned in one way or another to tank 4. If marble is picked up as a neutralizing agent, you can use the pressure of carbon dioxide released to pump the solution. In this case, between kos. 62866-2 -

The buffer vessel 7 must also be included in the well / receiver 6, into which the calcium chloride solution is collected during pumping. As the marble or lime dissolves, water is added to the system and a portion of the calcium chloride solution is withdrawn to maintain a constant salt concentration and to keep the total volume of the solution unchanged. The temperature of the mixture during chlorination should be kept 50-60 °. The reaction proceeds rather quickly, and the productivity of the apparatus is limited by the practical effectiveness of the washing of hydrochloric acid and the power of the coolers. The degree of chlorination can be adjusted to 90 percent or more, but with a high degree of chlorination, the amount of by-products in chloroacetone increases. To obtain a cleaner product, it is recommended to stop chlorination at a 50–60% chlorine consumption level from the theoretically required amount.

Subject invention

Claims (2)

1. A method of acetone, characterized in that an aqueous calcium chloride solution is passed through the chlorinated liquid in order to remove hydrogen chloride produced during the chlorination. 2. Acceptance of the method according to claim 1, that is, and with the fact that, in order to carry out a continuous process, and Cetone, chlorine and calcium chloride solution are introduced into the reaction space, and the reaction products are removed from him continuously.