Method for separating and refining high purity trimethylamine

Abstract

The invention relates to a separating and refining method of high-purity trimethylamine through abstraction with extraction tower and distillation with trimethylamine fractionating tower and dewatering with dehydration tower, which comprises the following parts: recycling circulating water as extractant by extraction tower, producing trimethylamine with more than 97% mass concentration to enter the trimethylamine fractionating tower to distill, recycling after abstracting tower kettle liquid into the dehydration column to reclaiming methylamine dimethylamine and carbinol, abstracting after the returning of feed liquid on top of the tower of trimethylamine fractionating tower and the tower kettle feed liquid, producing the high-purity trimethylamine ( the mass concentration is more than 99. 9%, the methylamine and the dimethylamine are less than200ppm) through side line of the trimethylamine fractionating tower. The new technology displays merits of being with high rating product and less abstraction water (only needed 1 / 2-2 / 3 of common usage), which has low energy consumption (totally saved about 15-30 steamer) and flexible operation and high reliability and so on.

Description

technical field [0001] The invention relates to a method for refining and separating high-purity trimethylamine. Background technique [0002] Trimethylamine is an important chemical raw material, which can be used in the manufacture of choline chloride, ion exchange resins, rubber additives, explosives, chemical fiber solvents, surfactants, photosensitive materials, developers, plant growth hormones, dwarf Strongin, etc., among which the export part is mainly used to produce choline chloride. During the reaction to generate choline chloride, mono- and dimethylamine contained in trimethylamine will generate carcinogens in side reactions, so their content must be controlled. In 2007, the European Union issued a new standard for choline chloride products, which clearly stipulates that the content of mono- and dimethylamine in trimethylamine must be less than 200ppm. This puts forward higher requirements for domestic trimethylamine production enterprises. At present, the tri...

AI Technical Summary

Problems solved by technology

To obtain high-quality trimethylamine products, the requirements for the extraction tower are very high: firstly, the number of theoretical plates for separation must be sufficient; secondly, the temperature of the extraction water must be strictly controlled at around 90°C, high temperature will reduce the separation performance, and low temperature will increase the energy Consumption; re-extraction water consumption is very large, resulting in a large amount of waste water, although it can be recycled and reused, but the energy consumption is also greatly increased; the location of the extraction water inlet is difficult to grasp

These have led to the unsatisfactory situation that the separation effect of the extraction tower is faced by the trimethylamine production enterprises.

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