A kind of efficient and environment-friendly diketene production process

Abstract

The invention discloses a high-efficiency and environment-friendly production process of diketene, which comprises the following steps: (1) gasifying acetic acid aqueous solution into acetic acid gas, then mixing it with a catalyst, and cracking it in a cracking furnace at a temperature of 680-698°C to produce ketene Gas, control the outlet pressure of the cracking furnace to an absolute pressure value of 2-20KP; (2) The purified ketene gas is transported to the absorption device through a vacuum pump, and the pressure before and after the pump is controlled to be 2-20KP and 100-120KP respectively , control the temperature difference of the absorption liquid to be less than 10°C; (3) put the absorption liquid into the high-temperature and low-temperature polymerization tanks for primary and secondary polymerization to obtain the crude product diketene; (4) carry out vacuum distillation of the crude product diketene to obtain diketene Finished product; (5) Under the action of the combustion-supporting oxidizing gas medium, the conveying pressure is controlled at 6-10Kgf / Cm2, and the rectification residue is conveyed to the combustion furnace for oxidation treatment. The above process has few side reactions, high product yield and no solid waste.

Description

technical field [0001] The invention relates to a production process for producing diketene by thermal cracking with acetic acid as raw material. Background technique [0002] Diketene, also known as diketene, is a colorless or light yellow liquid with a strong pungent odor. Because diketene contains two double bonds in its structure and is highly unsaturated, it has high chemical activity and excellent reaction in organic synthesis. It is an important intermediate and acetoacetylating agent in organic synthesis, and is widely used in medicine, pesticides, dyes, food and other industries. [0003] The acetic acid cracking method is a commonly used method to produce diketene. The production process of the acetic acid cracking method is as follows: the acetic acid aqueous solution with a mass concentration of about 92% is heated and vaporized, and then mixed with a phosphate aqueous solution catalyst with a mass concentration of 10% and enters together. The preheating section...

AI Technical Summary

Problems solved by technology

[0004] The shortcoming of above-mentioned acetic acid cracking method to produce diketene technology is: one, in the acetic acid cracking process can produce more by-products such as carbon monoxide, carbon dioxide, methane; High polymers such as tetraketene ketone affect the quality and yield of the final product diketene; 3. A large amount of solvents are used in the treatment of rectification residue, which increases the treatment cost and the pressure of environmental protection.