Separation and purification method and device for extracting and purifying piperidinol product from piperidone hydrogenation reaction solution

Abstract

The invention discloses a separation and purification method and a device for extracting and purifying a piperidinol product from piperidone hydrogenation reaction solution, and the method comprises the following steps: (a) leading piperidinol crude product raw material solution into a feed inlet of a piperidone recovery distillation column, discharging light components of piperidone, acetonine and the like from the top of the piperidone recovery distillation column, then condensing by a recovery condenser, leading part of the light components to return and simultaneously extracting part of the light components as a piperidone product; and (b) sending the materials extracted from the bottom part of the piperidone recovery distillation column into the feed inlet of a piperidinol rectification column, extracting gas phase piperidinol from the top of the piperidinol rectification column, condensing the gas phase piperidinol by the condenser, then leading one part to return, simultaneously extracting the other part as a product, heating stillage residue part discharged from the bottom of the piperidinol rectification column by a reboiler at the bottom of the piperidinol rectification column, then forming the gas phase, returning into the column and simultaneously discharging one part as waste liquid. The adoption of the method can obtain the high-purity piperidinol product (above 99.5% by weight) at one time and recover the piperidone product.

Description

technical field [0001] The invention relates to a separation and purification method for purifying piperidinol products from a piperidone hydrogenation reaction solution, and also relates to a separation and purification device for purifying piperidinol products from a piperidone hydrogenation reaction solution. Background technique [0002] Such as figure 1 Shown traditional piperidinol (2,2,6,6-tetramethyl-4-piperidinol) production technique is to use acetone as basic raw material earlier, obtain piperidone after reaction, then piperidone (2,2,6,6-Tetramethyl-4-piperidone) is hydrogenated to obtain the crude piperidinol, which is a mixture of components such as piperidinol, piperidone and acetonin involved in the present invention. After the solution is simply removed from alcohol (at this time, the mass percentage of piperidinol is about 90%), the first crystallization is carried out to obtain 95%-97% of piperidinol. Then, after secondary crystallization, more than 99.5...

AI Technical Summary

Problems solved by technology

Due to the shortcomings of the crystallization unit, such as long operation process, many equipment, large material loss, and high labor intensity, more piperidinol products are taken away by the crystallization mother liquor after the two crystallization processes, which will inevitably reduce the single-cycle yield of the product, and the product per ton The consumption of acetone is relatively large

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