Preparation method of neutral alkyl calcium salicylate

Abstract

The invention relates to a preparation method of a salicylic acid compound, particularly a preparation method of a neutral alkyl calcium salicylate, which comprises the following steps: evenly mixing alkyl phenol, calcium hydroxide, accelerator and diluent oil, introducing nitrogen, and reacting at 100-110 DEG C under the pressure of 2-3 MPa for 60 minutes; and carrying out vacuum distillation, introducing carbon dioxide gas, reacting at 30 DEG C under the pressure of 4 MPa for 120-180 minutes, diluting, carrying out centrifugal separation, and carrying out vacuum distillation to obtain the neutral alkyl calcium salicylate. In the invention, the calcium hydroxide is directly used for neutralization reaction instead of sodium hydroxide, and the alkyl calcium salicylate normal salt product can be obtained by carboxylation reaction, thereby saving the steps of alkyl sodium salicylate acidization, alkyl salicylic acid deposition water diversion, alkyl salicylic acid metallization reaction and the like in the original technique, and greatly lowering the production cost.

Description

technical field [0001] The invention relates to a preparation method of a salicylic acid compound. Background technique [0002] Alkyl salicylate is one of the earliest lubricating oil detergents that appeared in the early 1940s. It has good high-temperature detergency, acid neutralization ability and high thermal stability, as well as certain low-temperature dispersion ability and anti-oxidation, Anti-corrosion performance, especially suitable as a detergent for various diesel engine oils. The preparation process of traditional alkyl salicylate is relatively complicated. The preparation of alkyl salicylate with alkylphenol as the initial raw material is divided into two parts: the preparation reaction of raw material alkyl salicylic acid and the metallization reaction. There are five, Six-step reaction, more than ten procedures, the process is very complicated, resulting in high production costs and serious environmental problems. Although domestic and foreign researchers...

AI Technical Summary

Problems solved by technology

The preparation process of traditional alkyl salicylate is relatively complicated. The preparation of alkyl salicylate with alkylphenol as the initial raw material is divided into two parts: the preparation reaction of raw material alkyl salicylic acid and the metallization reaction. There are five, Six-step reaction, more than ten procedures, the process is very complicated, resulting in high production costs and serious environmental problems

Although domestic and foreign researchers have made many improvements and improvements to the preparation process over the years, they mainly focus on the optimization of the high alkalinity process, the hydrolysis of alkyl salicylate and the investigation of processes such as alkylation of salicylic acid. , did not fundamentally solve the problem