## 1 Introduction  
Extractive distillation (ED) is a reliable method employed for the separation and purification of azeotropic mixtures or mixtures characterized by low relative volatility [1]. In the process of ED, the relative volatility of these mixtures can be augmented by incorporating a selective extractive agent [2, 3]. As a result, ED is capable of effectively separating alcohol-water azeotropic mixtures that are not separable through conventional distillation techniques. Typically, the ED process comprises two primary components: an extractive distillation column (EDC) and a solvent recovery column (SRC). It is noteworthy that in specific instances involving ethanol/water, propanol/water, or butanol/water mixtures, water is present in excess within the fermentation broth. To minimize energy consumption and economic costs associated with the conventional extraction distillation (ED) process, excess water from the feed is removed using a preconcentration column (PC) before entering the extraction distillation column (EDC) [4]. This innovative approach, which incorporates a preconcentration column into the distillation process, is referred to as the TCED process [5]. This offers researchers the opportunity to design and explore processes in which the heat integration of the PC with the ED column or/and SRC could be achieved [5; 6; 7]. Europe is proposing that C2-C4 bio-alcohols play an increasingly important role in the formulation of advanced fuels as renewable energy for transport [8; 9; 10]. However, the production of these bio-alcohols must be ensured with the lowest possible energy consumption [11]. In the dehydration of these alcohols, the flexibility of the ED process in both design and operation has attracted the attention of researchers [12; 13]. The essential step in the design of bio-alcohol dehydration processes by ED is the choice of the most suitable solvent for performing the separation. In addition to the selection of the solvent, for a well-designed ED process, it is very important to obtain the purities required by the process with low energy consumption and minimal solvent losses [14]. Moreover, identifying the most favorable operating parameters of the ED columns to meet the process constraints is a complex task and can only be achieved with the help of process simulators. Our attention is focused on the dehydration of isopropyl alcohol (IPA) to obtain fuel grade. It is well known that the isopropanol (IPA)-water mixture forms a minimum-boiling azeotrope at 87.8 wt.% at 353.55 K, under atmospheric pressure. Therefore, a viable option for the dehydration of IPA is the ED process. Studies in recent decades have reported investigations into the dehydration of IPA by extractive distillation using ethylene glycol (EG) and dimethyl-sulfoxide (DMSO) as solvents [10]. [PERSON] and [PERSON] [15] investigated the IPA dehydration process by extractive distillation with DMSO. The design and control of the process operating parameters were performed for a feed flow rate of 100 kmol/h, equimolar IPA/water binary, in a conventional ED process with EDCs and SRCs. The purpose of their investigation was to achieve 99.9999 mol% of IPA in the distillate flow of the EDC and 99.9 mol% of water in the distillate of the SRC. The ultrahigh purity in IPA is dictated by the usage of IPA in the semiconductor industry. Even though they demonstrated the feasibility of using DMSO as a solvent, the constraints related to the purity of IPA led to an ED process with a very high EDC, which would imply construction problems. Also, the authors report the need for high-pressure steam for both reboilers. [PERSON] and [PERSON] [1] demonstrated the feasibility of TCED process for IPA/water separation from 250 kmol/h feed flow rate with 28.6 mol% of IPA using DMSO as a solvent. Then, they studied several types of multi-effect heat integration and several types of solvent sensible heat recovery. Their final conclusion is that heat integration is a way to reduce the energy requirement of a TCED process.