Intensified alternative to purify methyl-Ethyl ketone in a framework of green process

Methyl-Ethyl Ketone (MEK) is a promising bulk chemical due to its several applications. MEK can be produced by hydrogenation of 2, 3-Butanediol, a chemical previously produced by fermentation. As hydrogenation results, the output is composed of water, isobutyraldehyde, 2, 3-Butanediol, and Methyl ethyl ketone. Because of the thermodynamic interactions, two azeotropes are formed; consequently, the purification of that mixture is challenging. Current needs promote the generation of alternatives with good economic and environmental performance, however, inherent safety and good controllability must also be accomplished. In this study an intensified process is proposed to reduce the energy investment for MEK purification. The alternative is a hybrid process that combines the advantages of using a liquid-liquid extraction column for handling the azeotropes aforementioned. Additionally, this proposal is compared with four alternatives previously proposed based only on distillation. All alternatives were modeled in Aspen Plus and were optimized considering four targets, the total annual cost, the eco-indicator 99, the individual risk, and the condition number as economic, environmental, safety and controllability indexes, respectively. As a result, interesting trends among objectives and design variables were found. Additionally, the intensified design reported an energy investment of 6.78 MJfuel/kg(MEK), and the best pure distillation alternative 35.5 MJ(fuel)/Kg(MEK). (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

MEK is a promising bulk chemical with numerous applications, but its purification process faces challenges due to the formation of azeotropes. Therefore, a intensified process has been proposed to reduce the energy investment for MEK purification and replace traditional distillation methods. Comparison results showed that the intensified design performed excellently in terms of energy investment.