Semnan University Press Applied Chemistry Today 2981-2437 20 74 2025 03 21 Comparative Evaluation of the Extractive Desulfurization of Liquid Fuel Using Deep Eutectic Solvents Containing Triethanolamine with Dual Role Hydrogen Bond Donor-Hydrogen Bond Acceptor Comparative Evaluation of the Extractive Desulfurization of Liquid Fuel Using Deep Eutectic Solvents Containing Triethanolamine with Dual Role Hydrogen Bond Donor-Hydrogen Bond Acceptor 281 296 9783 10.22075/chem.2025.36942.2346 FA Farinaz Khaleghi Department of Chemistry, Faculty of Sciences, University of Zanjan, Zanjan, Iran Mahboobe Behroozi Department of Chemistry, Faculty of Sciences, University of Zanjan, Zanjan, Iran Journal Article 2025 02 19 Sulfur in fuel is one of the main sources of pollutants that cause environmental problems. In addition, the presence of sulfur impurities leads to corrosion problems in refinery units and deactivation of the catalyst used in refineries; therefore, desulfurization of fuel is very necessary. The use of green technologies to solve this problem is of interest to many researchers. Deep eutectic solvents (DES) are considered as solvents similar to ionic liquids and have attracted increasing attention in separation and extraction processes due to their features such as environmental compatibility and very low price. In this study, a deep eutectic solvent (DES) was prepared by mixing triethanolamine (TEOA) as the hydrogen bond donor (HBD) and choline chloride (ChCl) as the hydrogen bond acceptor (HBA). This DES was then used in extractive desulfurization to remove thiophene (Th). The results were compared with those obtained when TEOA acted as the HBA in the DES and the efficiency of TEOA in both HBD and HBA roles in desulfurization was evaluated. Response surface methodology (RSM) was used to model and optimize the extraction process. Three operating parameters affecting desulfurization, the DES component ratio (HBA: HBD), the initial sulfur content, and the mass ratio of DES to model fuel (DES:MF), were selected. Under optimal operating conditions for both DES, the maximum extraction efficiency in one stage was 70.3 and 71.8%, respectively. Sulfur in fuel is one of the main sources of pollutants that cause environmental problems. In addition, the presence of sulfur impurities leads to corrosion problems in refinery units and deactivation of the catalyst used in refineries; therefore, desulfurization of fuel is very necessary. The use of green technologies to solve this problem is of interest to many researchers. Deep eutectic solvents (DES) are considered as solvents similar to ionic liquids and have attracted increasing attention in separation and extraction processes due to their features such as environmental compatibility and very low price. In this study, a deep eutectic solvent (DES) was prepared by mixing triethanolamine (TEOA) as the hydrogen bond donor (HBD) and choline chloride (ChCl) as the hydrogen bond acceptor (HBA). This DES was then used in extractive desulfurization to remove thiophene (Th). The results were compared with those obtained when TEOA acted as the HBA in the DES and the efficiency of TEOA in both HBD and HBA roles in desulfurization was evaluated. Response surface methodology (RSM) was used to model and optimize the extraction process. Three operating parameters affecting desulfurization, the DES component ratio (HBA: HBD), the initial sulfur content, and the mass ratio of DES to model fuel (DES:MF), were selected. Under optimal operating conditions for both DES, the maximum extraction efficiency in one stage was 70.3 and 71.8%, respectively. https://chemistry.semnan.ac.ir/article_9783_4c7080ba042d3e2ed9f73903e5fde803.pdf