Citation: Torres Cantero, C.A.; Pérez Zúñiga, R.; Martínez García, M.; Ramos Cabral, S.; Calixto-Rodriguez, M.; Valdez Martínez, J.S.; Mena Enriquez, M.G.; Pérez Estrada, A.J.; Ortiz Torres, G.; Sorcia Vázquez, F.d.J.; et al. Design and Control Applied to an Extractive Distillation Column with Salt for the Production of Bioethanol. Processes 2022, 10, 1792. https://doi.org/10.3390/pr10091792 Academic Editors: Antonio D. Moreno and Paloma Manzanares Received: 2 August 2022 Accepted: 24 August 2022 Published: 5 September 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). processes Article Design and Control Applied to an Extractive Distillation Column with Salt for the Production of Bioethanol Carlos Alberto Torres Cantero 1,2 , Ricardo Pérez Zúñiga 3 , Mario Martínez García 4, *, Silvia Ramos Cabral 4 , Manuela Calixto-Rodriguez 5 , Jorge Salvador Valdez Martínez 5 , Mayra Guadalupe Mena Enriquez 6 , Abraham Jashiel Pérez Estrada 7 , Gerardo Ortiz Torres 4 , Felipe de J. Sorcia-Vázquez 4 , Azael García Rebolledo 2 and Jesse Yoe Rumbo Morales 4 1 Tecnológico Nacional de Mexico Campus Colima, Av. Tecnológico # 1, Col. Liberación, Villa de Álvarez 28976, Colima, Mexico 2 Facultad de Ingeniería Mecánica y Eléctrica de la Universidad de Colima, Carretera Colima-Coquimatlan Km 9, Valle de las Huertas, Coquimatlán 28400, Colima, Mexico 3 Departamento en Ciencias Computacionales e Ingenierías, Sistema de Universidad Virtual de la Universidad de Guadalajara, Av. Juárez No. 976, Colonia Centro, Guadalajara 44100, Jalisco, Mexico 4 Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km 45.5, Ameca 46600, Jalisco, Mexico 5 División Académica de Mecánica Industrial, Universidad Tecnológica Emiliano Zapata del Estado de Morelos, Avenida Universidad Tecnológica No. 1, Col. Palo Escrito, Emiliano Zapata 62760, Morelos, Mexico 6 Centro de Investigación Multidisciplinario en Salud, Departamento de Ciencias Biomédicas, Centro Universitario de Tonalá, Tonala 45425, Jalisco, Mexico 7 School of Engineering and Sciences, Tecnologico de Monterrey, Monterrey 64849, Nuevo Leon, Mexico * Correspondence: mario.mgarcia@academicos.udg.mx Abstract: Extractive distillation with salts, unlike other dehydration technologies, is better due to the null toxicity that exists in the distillate, since salt cannot be evaporated. With this distillation technology, it is possible to obtain a high concentration of ethanol, however, there are still problems in the control of the distillation columns in the presence of disturbances. The present work deals with the simulation and control of an extractive distillation column using CaCl 2 as a separating agent, for which the Aspen Dynamics ® simulator is used. The measurement and control of the ethanol composition are carried out by means of temperature, in addition, four control structures are evaluated and compared. These structures are L, D, LV, and DV, which are the most common in conventional distillation, and their performance is measured by means of deterministic indicators applying changes (disturbances) of composition and the flow rate in the main feed of the column. The most relevant results of this work lead to the fact that by applying a controller, it is possible to maintain the desired purity above the international purity standards (99% ethanol) that govern biofuels. Keywords: bioethanol; salt; control; extractive distillation column 1. Introduction In recent years, research has focused on the search for alternative sources of renewable energy. This is to reduce the dependence on fossil fuels and the greenhouse gas emissions derived from them. To reduce this dependence on fossil fuels, bioethanol has been intro- duced, produced through fermentation technologies from sugars and starches from raw materials, such as cane, corn, wheat, beet, barley, and sorghum, among others. This type of bioethanol production from these raw materials is known as first-generation biofuel, there are also second- and third-generation biofuels, which use materials, such as plants, trees, animal waste, algae, marine plants, or any other type of vegetable or animal waste. In addition, another type of raw material that is being used recently is the food waste that we generate throughout the food supply chain, from production to human consump- tion. This type of raw material is known as biomass and is divided into vegetable and lignocellulosic [1–7]. Processes 2022, 10, 1792. https://doi.org/10.3390/pr10091792 https://www.mdpi.com/journal/processes