Technological process for continuously producing sec-butyl alcohol by direct hydration of n-butene

Abstract

The invention relates to a technique method of the continuous production of 2-butanol by the direct hydration of n-butene, belonging to the technical field of petrochemical industry. The invention comprises the steps that under the existence of the catalyst of strong acid ion exchange resin, fresh raw material of the n-butene and a cycling n-butene are mixed up and enter a hydration reactor for a hydration reaction, and then enter a separation unit of crude products for separation; a refining unit of the n-butene is additionally arranged; one part of the unreacted n-butene which is separated from the separation unit of crude products is used as the cycling n-butene and is returned to the hydration reactor for further hydration reaction and the other part is sent to the refining unit of the n-butene for the rectification and n-butene is recycled after the removal of butane to be used as the fresh raw material of the n-butene continually. The method has the advantages of improving recycling, improving the volumetric efficiency of the hydration reactor, improving the yield of 2-butanol greatly, reducing ineffective circulation and reducing the consumption of energy, thus realizing the zero discharge of the n-butene with high yield and low energy consumption.

Description

technical field [0001] The invention relates to a process for continuously producing sec-butanol through direct hydration of n-butene, which belongs to the technical field of petrochemical industry. Background technique [0002] In 1984, the former Federal Republic of Germany successfully developed a new process of producing sec-butanol by direct hydration of n-butene with a strong acidic ion exchange resin as a catalyst, and built a 60kt / a direct hydration industrial device with a reaction temperature of 150-170°C. The reaction pressure is 5-7MPa, the molar ratio of water / n-butene is 15:1~20:1, most of the sec-butanol produced by the reaction is dissolved in C 4 in hydrocarbons. The reaction product enters the de-C after the liquid-liquid separator separates the water layer. 4 The tower and the bottom of the tower are crude sec-butanol without water, which is refined in the subsequent process. A part of the unreacted n-butene distilled from the tower is recycled back to ...

AI Technical Summary

Problems solved by technology

However, the sec-butanol recycled to the main reactor will affect the chemical balance of the hydration reaction and reduce the per-pass conversion rate of n-butene in the main reactor, and the effect is not ideal

[0005] The above technologies have their own advantages, but they all have the disadvantages of low total conversion rate and large loss of raw materials. Harmful impurities such as isobutylene and dienes in the discharged raw materials are all cleaned up during the hydration reaction process, which belongs to butylene-containing only It is a pity to lose the high-quality raw materials of alkane and n-butene

In order to avoid excessive loss of raw materials, the content of n-butene raw materials entering the hydration reactor in the above process is generally low

Controlled at about 80% of the weight concentration, the volumetric efficiency of the hydration reactor is low, which affects the output of sec-butanol

A large amount of butane in the reaction material is repeatedly heated, cooled, evaporated, and condensed during the cycle, resulting in high energy consumption of the product

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