Abstract
Sulfur compounds are found in crude benzene from coke production. One of these compounds is thiophene. Extractive distillation (ED) with dimethylformamide as a separating agent can be used to remove it from crude benzene. The relative volatility in the benzene–thiophene binary system increases in the presence of dimethylformamide from 1.13 to 1.46–2.18. The purpose of this work is to study the possibility of using a scheme that includes a complex extractive column (EC) with side withdrawal in the vapor phase. New schemes of ED have been synthesized and mathematical modeling and their optimization have been carried out. It is shown that the proposed scheme of ED provides a decrease in energy consumption by 29.5% and the amount of circulating extractive agent (E) by 47.8%. At the same time, the requirements for the quality of benzene purification and its losses with the thiophene fraction are met.
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This work was carried out with financial support from the Ministry of Education and Science of the Russian Federation as part of the State Task of MIREA–Russian Technological University, topic no. 0706-2020-0020.
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Anokhina, E.A., Yakutin, R.I. & Timoshenko, A.V. Purifying Benzene from Thiophene by Extractive Distillation Using Columns with Side Withdrawal in the Vapor Phase. Theor Found Chem Eng 55, 880–887 (2021). https://doi.org/10.1134/S0040579521040205
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DOI: https://doi.org/10.1134/S0040579521040205