A method for preparing dimer acid by temperature-programmed oleic acid dimerization

Abstract

The invention discloses a method for preparing dimer acid by temperature-programmed dimerization of oleic acid. Raw materials, catalysts and co-catalysts are added together into a clean reactor; After the air in the reaction kettle is filled, a certain pressure of decarboxylation inhibitory gas is introduced, and the heating is stirred; after setting the first reaction temperature, the heating equipment is turned on, and after the temperature reaches the set temperature, the reaction is performed for a certain period of time, and then the heating power is adjusted to make the reaction The temperature rises to the reaction temperature of the second stage, and the reaction is continued for a certain period of time. After the reaction is finished, the reaction product obtained is centrifuged and filtered to remove the catalyst to obtain the initial dimer acid product. The new process for preparing dimer acid by temperature-programmed oleic acid dimerization of the present invention has short reaction time, less catalyst consumption, less solid waste catalyst discharge, less product loss, and the conversion rate of oleic acid is greater than 66%, which has good economic benefits and promotion prospects.

Description

technical field [0001] The invention belongs to the improvement technology of dimer acid polymerization process, in particular to a method for preparing dimer acid by temperature-programmed dimerization of oleic acid. Background technique [0002] Due to its unique physical and chemical properties, dimer acid has been widely used in many industrial fields. With the expansion of the application range of dimer acid, the demand for dimer acid is increasing year by year. The main raw material for the production of dimer acid is waste oil, which has low cost and wide sources. Today, when petroleum resources are increasingly depleted, the development and production of some chemical products using dimer acid as raw material can eliminate or reduce the impact of these products on petroleum resources. rely. [0003] At present, the catalysts used in the industrial production of dimer acid are activated clay catalysts. Limited to the technical and economic benefits of activated clay...

AI Technical Summary

Problems solved by technology

This action not only pollutes the environment, wastes land resources and endangers groundwater quality, but also leads to the loss of dimer acid

To solve this problem, the fundamental method is to find a catalyst that can be recycled or a catalyst with higher catalytic activity or an eco-friendly catalyst, but this process will be very long. Therefore, the current practical method is to improve the process route, On the premise of ensuring the yield and economic benefits, reduce the amount of activated clay as much as possible

[0004] In addition, in the existing process, the amount of catalyst required for the general reaction is more than 10%, and the reaction time is more than 4 hours, which has the disadvantages of longer reaction time and more catalyst amount.

The reason is that due to the presence of linolenic acid in the raw material, it is easy to oxidize, and the conjugated isomerization of oleic acid in the reaction produces a heat-sensitive carbon-carbon double bond, so the temperature of the polymerization reaction should not be too high, otherwise it is easy to carbonize, and fatty acids will also co-exist. The decarboxylation reaction of valence bond breaking will make the product darker and reduce the quality of dimer acid

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