New method for producing dihydromyrcene

Abstract

The invention discloses a new method for producing dihydromyrcene through partial thermal isomerization of pinane, which mainly comprises the following steps of: performing partial thermal isomerization on the pinane in a cracking furnace to generate the dihydromyrcene, performing heat exchange between the dihydromyrcene, unreacted pinane and a reaction byproduct out of the cracking furnace and a raw material pinane entering the cracking furnace, and making the dihydromyrcene, unreacted pinane and the reaction byproduct enter a rectifying tower for rectification; and after the rectification of the rectifying tower, obtaining the pure dihydromyrcene on the tower top, obtaining heavy components on the bottom of the tower, extracting pinane-containing streams with high concentration from the side of the rectifying tower and returning the pinane-containing streams serving as a raw material for thermal isomerization. The method has the advantages that: a partial cracking-rectifying separation process is adopted to improve the selectivity (over 80 percent ) of generating the dihydromyrcene, which is improved by about 10 percent than that under the condition of single-pass overall conversion; meanwhile, the high-temperature materials at the outlet of the cracking furnace exchange heat with the raw material pinane, the heat of the system is fully utilized, and the energy consumption of the whole system is reduced.

Description

technical field [0001] The invention belongs to the field of chemical technology, and in particular relates to a method for producing dihydromyrcene by using pinane as a raw material. Background technique [0002] Pinane (2,6,6-trimethylbicyclo[3.1.1]heptane) is a monoterpene compound, which is obtained by hydrogenation of pinene in turpentine oil, and the main product di Hydrogen myrcene (Dihydromene, also known as dihydromyrcene) is a good intermediate for the synthesis of fragrances and medicines. It is of great significance to study the synthesis of its downstream products from dihydromyrcene, the main product of pinane cracking, for the comprehensive utilization of my country's rich turpentine resources. Hydrogenate α-pinene to produce α-pinene, and then undergo thermal isomerization to obtain dihydromyrcene, but the isomerization product of α-pinene is a mixture of various terpenes, and its boiling point difference is very small , and there are unreacted cis-pinane a...

AI Technical Summary

Problems solved by technology

Hydrogenate α-pinene to produce α-pinene, and then undergo thermal isomerization to obtain dihydromyrcene, but the isomerization product of α-pinene is a mixture of various terpenes, and its boiling point difference is very small , and there are unreacted cis-pinane and trans-pinane, because the boiling points of pinane and dihydromyrcene are very close, it is difficult to separate by rectification

If in order to improve the conversion rate of pinane, then the selectivity of generating dihydromyrcene is reduced again, causing the separation difficulty of by-product and dihydromyrcene

The high temperature reaction product from the cracking furnace must be cooled and condensed into the refining tower. If this part of heat is directly exchanged with the cooling medium, it will not only waste energy but also require cooling medium, which will increase the operating cost of the system.

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