Method for preparing SBA(sec-butyl alcohol) through hydrolysis with sec-butyl acetate

Abstract

A method for preparing sec-butyl alcohol through hydrolysis with SBA(sec-butyl alcohol)comprises steps as follows: (1) SBA is sent to a first hydrolysis reactor to react after being mixed with water; (2) a mixture after the reaction is sent to the lower part of a deacidification tower for separation, and separated acetic acid falls into the tower bottom; (3) a strand of material is extracted out of an SBA enrichment area of the deacidification tower and sent to an SBA refinement tower, an entrainer and water are added, an azeotrope formed by water, sec-butyl acetate and part of SBA is evaporated to the tower top, one part of oil phase is subjected to reflux after condensation layering, the other part returns to a reaction system for recycling with an aqueous phase, most of SBA falls into the tower bottom, and the SBA product is produced from the tower bottom. The SBA separated with the method has the purity of 99% or above, the purity of acetic acid separated by the deacidification tower is 97% or above, the yield of SBA is 70% or above, meanwhile, the method adopts a simple process and is simple to operate, and energy consumption is lower.

Description

technical field [0001] The invention relates to a method for preparing sec-butanol by hydrolysis of sec-butyl acetate. Background technique [0002] Secondary butanol (SBA), also known as second butanol, methyl ethyl carbinol, other butanol, 2-butanol, is a colorless, transparent, flammable liquid with a wine-like smell. SBA is used as a solvent in industry, co-solvent with methanol, can be used as a component to increase the octane number of gasoline, and can also be used to produce plasticizers, mineral dressing agents, herbicides, sec-butyl esters, etc., but the most important application is The production of methyl ethyl ketone accounts for about 90% of the total consumption. At present, the relatively mature methods in the industry include the indirect hydration method of n-butene and the direct hydration method of n-butene. The traditional process for preparing sec-butanol is sulfuric acid indirect hydration, which includes four steps: esterification, hydrolysis, rec...

AI Technical Summary

Problems solved by technology

The disadvantage is that the single-pass conversion rate of n-butene is low, only about 6%, and the requirements for raw materials are relatively strict. If the n-butene content of the C4 raw material used in the direct hydration process is greater than 90%, it may be directly hydrated to SBA, if the B-B grade fraction with lower n-butene content is directly reacted, the project cost will be increased due to its low conversion rate and high circulation rate, so extractive distillation or molecular sieve separation should be carried out first, and pre-purification should be carried out to achieve the maximum reduction. purpose of production cost

In this invention, the process is relatively long, and the obtained methyl acetate product is a crude ester product with a mass fraction of about 82% and low purity. However, in the sec-butanol refining tower, since sec-butanol and sec-butyl acetate can form an azeotrope , the boiling point of the azeotrope is 99.6 ° C, and the boiling point of sec-butanol is 99.5 ° C, so, in this column, sec-butanol and sec-butyl acetate cannot be separated well, and high-purity sec-butanol cannot be obtained basically alcohol

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