Oil desulfurization using deep eutectic solvents as sustainable and economical extractants via liquid-liquid extraction: Experimental and PC-SAFT predictions

Abstract The reduction of the sulfur content in crude oil is of utmost importance in order to meet the stringent environmental regulations. Thiophene and its derivatives are considered key substances to be separated from the crude oil. In previous works, six deep eutectic solvents (DESs) based on tetraethylammonium chloride, tetrahexylammonium bromide and methyltriphenylphosphonium bromide as hydrogen bond acceptors (HBAs) and polyols (ethylene glycol and glycerol) as hydrogen bond donors (HBDs) were successfully applied for the extraction of thiophene from {n-alkane + thiophene} mixtures via liquid-liquid extraction. One of the objectives of this work was to study the effect of the aliphatic hydrocarbon type/length (e.g. n-hexane vs n-octane) on the extraction performance of the same DESs. Extraction performance was evaluated by the selectivity and the thiophene distribution coefficient. Based on new experimental data, higher selectivities and lower thiophene distribution coefficients were obtained when thiophene was extracted from n-octane instead of n-hexane. Another objective was to predict the phase behavior of the ternary systems {n-alkane + thiophene + DES} using Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT). The PC-SAFT “pseudo-pure component” approach was applied, in which a DES was considered as a pseudo-pure compound (not a mixture). The pure-component parameters of the DESs were obtained by fitting to liquid density data, which were measured at temperatures between 298.2 K and 323.2 K. Binary interaction parameters were fitted to experimental binary LLE data for the systems {n-alkane + DES} and {thiophene + DES} at 298.2 K and atmospheric pressure, while the LLE data of the ternary systems {n-alkane + thiophene + DES} were fully predicted. It was found that the distribution coefficients and selectivity of the ternary systems containing DESs could be qualitatively well predicted using this model.

[1]  A. Arce,et al.  Phase behaviour of 1-methyl-3-octylimidazolium bis[trifluoromethylsulfonyl]imide with thiophene and aliphatic hydrocarbons: The influence of n-alkane chain length , 2008 .

[2]  François Jérôme,et al.  Deep eutectic solvents: syntheses, properties and applications. , 2012, Chemical Society reviews.

[3]  S. Azizian,et al.  Polyethylene glycol as a green solvent for effective extractive desulfurization of liquid fuel at ambient conditions , 2014 .

[4]  Maaike C. Kroon,et al.  Effect of the Type of Ammonium Salt on the Extractive Desulfurization of Fuels Using Deep Eutectic Solvents , 2018 .

[5]  Gabriele Sadowski,et al.  Perturbed-Chain SAFT: An Equation of State Based on a Perturbation Theory for Chain Molecules , 2001 .

[6]  B. Mokhtarani,et al.  Novel liquid–liquid equilibrium data for six ternary systems containing IL, hydrocarbon and thiophene at 25 °C , 2016 .

[7]  Sona Raeissi,et al.  Modeling the Phase Behavior of Carbon Dioxide Solubility in Deep Eutectic Solvents with the Cubic Plus Association Equation of State , 2017 .

[8]  F. Mjalli,et al.  The Novel Application of Hydrated Metal Halide ( SnCl 2 . 2 H 2 O ) – Based Deep Eutectic Solvent for the Extractive Desulfurization of Liquid Fuels , 2022 .

[9]  Sona Raeissi,et al.  A general viscosity model for deep eutectic solvents: The free volume theory coupled with association equations of state , 2017, Fluid Phase Equilibria.

[10]  J. Hrbek,et al.  Interaction of Sulfur with Well-Defined Metal and Oxide Surfaces: Unraveling the Mysteries behind Catalyst Poisoning and Desulfurization , 1999 .

[11]  Liquid–liquid equilibrium data for the systems {LTTM + benzene + hexane} and {LTTM + ethyl acetate + hexane} at different temperatures and atmospheric pressure , 2013 .

[12]  P. Uusi-Kyyny,et al.  Vapor-Liquid Equilibrium for Binary System of Thiophene + n-Hexane at (338.15 and 323.15)K and Thiophene + 1-Hexene at (333.15 and 323.15)K , 2006 .

[13]  Guangren Yu,et al.  Extractive Desulfurization of Fuel Oils with Thiazolium-Based Ionic Liquids , 2012 .

[14]  M. C. Kroon,et al.  Low-transition-temperature mixtures (LTTMs): a new generation of designer solvents. , 2013, Angewandte Chemie.

[15]  David L Davies,et al.  Novel solvent properties of choline chloride/urea mixtures. , 2003, Chemical communications.

[16]  A. Ait Kaci,et al.  Enthalpies molaires d'exces des melanges binaires thiophene et diethylsulfide avec n-alcanes , 2002 .

[17]  Christoph Held,et al.  Separation Performance of BioRenewable Deep Eutectic Solvents , 2015 .

[18]  M. Fahim,et al.  Removal of Dibenzothiophenes from Fuels by Oxy-desulfurization , 2009 .

[19]  F. Mjalli,et al.  Liquid–liquid equilibria for the ternary system (phosphonium based deep eutectic solvent–benzene–hexane) at different temperatures: A new solvent introduced , 2012 .

[20]  Qi Zhao,et al.  Extraction desulfurization process of fuels with ammonium-based deep eutectic solvents , 2013 .

[21]  Maaike C. Kroon,et al.  Aliphatic–Aromatic Separation Using Deep Eutectic Solvents as Extracting Agents , 2015 .

[22]  Christoph Held,et al.  PC-SAFT Modeling of CO2 Solubilities in Deep Eutectic Solvents. , 2016, The journal of physical chemistry. B.

[23]  Mohd Ali Hashim,et al.  Elimination of All Free Glycerol and Reduction of Total Glycerol from Palm Oil-Based Biodiesel Using Non-Glycerol Based Deep Eutectic Solvents , 2013 .

[24]  Z. Gomzi,et al.  Study of diesel fuel desulfurization by adsorption , 2010 .

[25]  S. Sandler,et al.  Using molecular orbital calculations to describe the phase behavior of cross-associating mixtures , 1998 .

[26]  A. Arce,et al.  Desulfurization of fuels by liquid–liquid extraction with 1-ethyl-3-methylimidazolium ionic liquids , 2013 .

[27]  Fabrice Diehl,et al.  On the hydrodesulfurization of FCC gasoline: a review , 2005 .

[28]  Jingjing Li,et al.  Deep Extractive Desulfurization with Arenium Ion Deep Eutectic Solvents , 2015 .

[29]  A. Arce,et al.  Ionic liquids on desulfurization of fuel oils , 2010 .

[30]  A. Arce,et al.  Desulfurization of fuel-oils with [C2mim][NTf2]: A comparative study , 2013 .

[31]  Chunshan Song,et al.  New design approaches to ultra-clean diesel fuels by deep desulfurization and deep dearomatization , 2003 .

[32]  Emma Lloyd Raven,et al.  Extraction of glycerol from biodiesel into a eutectic based ionic liquid , 2007 .

[33]  I. Babich.  Science and technology of novel processes for deep desulfurization of oil refinery streams: a review☆ ☆ , 2003 .

[34]  B. Mokhtarani,et al.  Phase Behavior of Nitrate Based Ionic Liquids with Thiophene and Alkanes , 2014 .

[35]  Jingjing Li,et al.  Green Carboxylic Acid-Based Deep Eutectic Solvents as Solvents for Extractive Desulfurization , 2016 .

[36]  Maaike C. Kroon,et al.  Deep eutectic solvents for highly efficient separations in oil and gas industries , 2017 .

[37]  C. Peters,et al.  Separation of Thiophene from Aliphatic Hydrocarbons Using Tetrahexylammonium-Based Deep Eutectic Solvents as Extracting Agents , 2017 .

[38]  D. Bose.  Design Parameters for a Hydro desulfurization (HDS) Unit for Petroleum Naphtha at 3500 Barrels per Day , 2015 .

[39]  P. Rasmussen,et al.  Liquid-liquid equilibrium data: Their retrieval, correlation and prediction Part I: Retrieval , 1979 .

[40]  Maaike C. Kroon,et al.  PC-SAFT modeling of CO2 solubilities in hydrophobic deep eutectic solvents , 2017 .

[41]  Zaira Maugeri,et al.  Ionic liquids in biotransformations: from proof-of-concept to emerging deep-eutectic-solvents. , 2011, Current opinion in chemical biology.

[42]  Rashid Abro,et al.  A review of extractive desulfurization of fuel oils using ionic liquids , 2014 .

[43]  P. Kulkarni,et al.  Deep desulfurization of diesel fuel using ionic liquids: current status and future challenges , 2010 .

[44]  M. L. Gorbaty,et al.  Direct determination and quantification of sulphur forms in heavy petroleum and coals: 1. The X-ray photoelectron spectroscopy (XPS) approach , 1990 .

[45]  G. Hutchings,et al.  Hydrodesulfurization of hindered dibenzothiophenes: an overview , 2000 .

[46]  Mohd Ali Hashim,et al.  Removal of Thiophene from Mixtures with n-Heptane by Selective Extraction Using Deep Eutectic Solvents , 2016 .

[47]  S. Sandler,et al.  Using Molecular Orbital Calculations To Describe the Phase Behavior of Hydrogen-Bonding Fluids† , 1997 .

[48]  Sona Raeissi,et al.  The friction theory for modeling the viscosities of deep eutectic solvents using the CPA and PC-SAFT equations of state , 2018 .

[49]  Chunshan Song.  An overview of new approaches to deep desulfurization for ultra-clean gasoline, diesel fuel and jet fuel , 2003 .

[50]  M. Hashim,et al.  The role of ionic liquids in desulfurization of fuels: A review , 2017 .

[51]  A. Arce,et al.  Hexyl dimethylpyridinium ionic liquids for desulfurization of fuels. Effect of the position of the alkyl side chains , 2012 .

[52]  Cor J. Peters,et al.  Prediction of the CO 2 Solubility in Deep Eutectic Solvents: A Comparative Study between PC-SAFT and Cubic Equations of State , 2017 .