Method for separating and purifying cyclododecatriene

Abstract

The invention provides a method for separating and purifying cyclododecatriene. The method comprises the following steps: dissolving a quenching agent in a solvent to prepare a quenching agent solution; mixing the quenching agent solution with a cyclododecatriene reaction solution, quenching in a quenching reactor to obtain a cyclododecatriene crude product; introducing the cyclododecatriene crudeproduct into a chelating resin tower at first, and then making the crude product sequentially pass through a catalyst removal unit, a heavy component removal unit, a solvent removal unit, a quenchingagent removal unit, a light component removal unit and a product refining unit in a distillation tower to obtain a cyclododecatriene product. According to the method, corrosion to equipment is reduced, the danger coefficient is low; the side reaction is reduced, the yield of cyclododecatriene is increased; the stability of CDT and other heat-sensitive substances in the separation process is improved, the purity of cyclododecatriene is improved; insoluble substances in a crude product can be avoided, so that the separation process is continuous, and industrial amplification is easy to realize.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a separation and purification method of cyclododecatriene. Background technique [0002] Cyclododecatriene, English name cyclododecatriene, referred to as CDT, is an important organic chemical intermediate, which is mainly used as a raw material for the synthesis of nylon 12, hexabromododecane, macrocyclic musk and spices. The preparation of cyclododecatriene in the industry is to use butadiene as a raw material and obtain it by reacting under the action of a homogeneous Ziegler-Natta catalyst. After the reaction is completed, the Ziegler-Natta catalyst is Quenching to inactivate it, followed by further isolation and purification. [0003] At present, in the prior art, there are mainly the following methods for quenching Ziegler-Natta catalysts: (1) patent document CN103420777A discloses a method for continuously synthesizing 1,5,9-cyclododecatriene, It adopts sodiu...

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Problems solved by technology

[0003] At present, in the prior art, there are mainly the following methods for quenching Ziegler-Natta catalysts: (1) patent document CN103420777A discloses a method for continuously synthesizing 1,5,9-cyclododecatriene, It adopts sodium hydroxide aqueous solution to quench the catalyst, and the reaction product removes the waste catalyst solid matter and butadiene polymer in the reactant through a thin-film evaporator, and then carries out vacuum distillation in a rectification tower to obtain 1,5,9 -Cyclododecatriene, but because the aluminum insolubles produced by the hydrolysis of alkyl compounds adhere to the thin film evaporator, which seriously affects the separation effect of the equipment and causes equipment failure, which is not conducive to industrial continuous production; and when cleaning the inside of the equipment, Because the catalyst residue at the bottom of the thin film evaporator is exposed to the air, it is easy to catch fire, and the operation risk is high

(2) Patent document CN105693455A discloses: with the methanol solution of sodium methoxide as quenching agent, the reaction solution is at first normal pressure distillation to remove low boiling point substances, then underpressure distillation, obtains cyclododecatriene product; Yet because sodium methoxide has Corrosive and unstable, high requirements for equipment and process operation, so the risk factor is high

(3) U.S. Patent Documents US3655795A and US3878259A disclose the use of gaseous ammonia as a catalyst system quencher, but since ammonia and organoaluminum compounds will form deposits, it is extremely unfavorable for subsequent separations

(4) Patent document JP-A-07-442496 uses methanol as a catalyst quencher, but methanol and catalyst solvent toluene are azeotropic, which increases the difficulty of subsequent separation; DE-A-1942729 uses methanol / HCl as a catalyst quencher , but the quencher is easy to react with CDT to form chlorinated cyclododecatriene, which affects the quality of cyclododecatriene

(5) Patent literature CN103265393A discloses a method for extraction and separation, comprising the following steps: first, distilling out most of the main product cyclododecatriene volatile components in the crude product, and then to the remaining volatile components at the bottom of the distillation tower Add the mixed extractant to the residue of the viscous mixture, heat and reflux to extract, obtain the distillate and the remaining oil, then add the distillate to the distillation tower, separate under reduced pressure, obtain the extractant separately, cool and settle the remaining oil, and make the poly Butadiene is crystallized, and finally, the crystals are separated by filtration, which has disadvantages such as large amount of extractant used, increased separation difficulty, high energy consumption, and serious side reactions.

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