Process for improving production device of dioctyl phthalate

Abstract

The invention relates to a process for improving a universal type plasticizer for the chemical industry, particularly to a process for improving a production device of dioctyl phthalate. The process is characterized by comprising the steps that solid flaky phthalic anhydride and capryl alcohol are added simultaneously from the top of a phthalic anhydride melting kettle, phthalic anhydride and capryl alcohol are fed according to a molar ratio of (0.8-1.0):1, the reaction temperature ranges between 135 DEG C and 155 DEG C, and the reaction time ranges between 2 hours and 2.5 hours. The process has the advantages that a process medium inside the improved phthalic anhydride melting kettle flows smoothly in the device and pipelines, no blocking phenomena exist again, and the continuous working time for operation can be improved; and the improved phthalic anhydride melting kettle can melt phthalic anhydride and also can generate unit esters, the technological process is simplified, the one-time investment for the device is reduced, the daily repair and maintenance operation for the device and the pipelines is reduced, the actual continuous production time for the device is increased, the production capacity for the device is improved greatly, and the product quality is improved.

Description

technical field [0001] The invention relates to an improved process for a chemical general-purpose plasticizer, and more specifically relates to an improved process for a dioctyl phthalate production device. Background technique [0002] Dioctyl phthalate (DOP) is a general-purpose plasticizer, which is produced by esterification with phthalic anhydride and octanol as raw materials under the action of a catalyst. Solid flaky phthalic anhydride needs to be completely melted in the phthalic anhydride melting tank before entering the esterification process. [0003] Phthalic anhydride has a high melting point. In order to prevent the molten phthalic anhydride from re-solidifying before reaching the esterification process, the delivery pipeline often adopts the method of steam jacket heating. The problem is that during the flow of molten phthalic anhydride in the pipeline, there will inevitably be areas with poor flow, which will lead to re-solidification of the molten phthalic...

AI Technical Summary

Problems solved by technology

The problem is that during the flow of molten phthalic anhydride in the pipeline, there will inevitably be areas with poor flow, which will lead to re-solidification of molten phthalic anhydride and partial blockage of the pipeline

As a result, the addition of phthalic anhydride was hindered, the esterification reaction was insufficient, and the final product could not meet the design quality requirements. In addition, the jacketed pipe was not only expensive, but also needed to be regularly unblocked after being blocked. It was difficult to clean, labor-intensive, and required frequent inspection and maintenance. Production cannot be carried out continuously for a long period, which directly affects the economic benefits of the device

Images