Investigation of Sulfolane Addition to Heat of H2S Absorption in Aqueous MDEA Solution Using Solubility Data

Document Type : Research Article


1 Department of Chemical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, I.R. IRAN

2 Gas Research Division, Research Institute of Petroleum Industry (RIPI), Tehran, I.R. IRAN


Aqueous alkanolamine solutions technology is one of the most important processes in natural gas sweetening. Water provides an implicit context for alkanolamine to absorb CO2 and H2S chemically. However, apart from their advantages, aqueous alkanolamine solution is not a good solvent for mercaptan removal and due to their innate exothermic reaction, it requires high reboiler duty performance in the desorption tower. Thereby it causes some undesirable side irreversible reactions such as decomposition of solvents, degradation so on. Nowadays mixture of aqueous alkanolamine solution and physical solvents such as sulfolane so-called hybrid solvents have been used to modify conventional aqueous alkanoleamine solvents. Hybrid solvents with optimum composition may possess both advantages of physical (SFL) and chemical (aqueous alkanolamine) solvents by which, not only CO2 and H2S would be absorbed chemically, but also mercaptan would be removed up to the allowed specification limit. In this work, the differential enthalpy related to H2S dissolution in both conventional (H2O – MDEA) and hybrid solvent (H2O - SFL – MDEA) were estimated from reported solubility data in the literature using Gibbs – Helmholtz equation. The process of differentiation was done after e-Pitzer modeling of experimental solubility data. As a result, the applied model provided sound results for solubility data in quaternary hybrid systems (ARD% equal to 5.4%), and also the addition of Sulfolane in MDEA – H2O system has a marginal effect on dissolution enthalpy of H2S.


Main Subjects

[1] حسینی جناب، مسیح، "تصفیه و فرآورش گاز طبیعی"، پژوهشگاه صنعت نفت، تهران (1392).
[2] Isaacs E.E., Otto F.D., Mather A.E., Solubility of Hydrogen Sulfide and Carbon Dioxide
in a Sulfinol Solution,
Journal of Chemical and Engineering Data, 22(3): 317-319 (1977).
[3] Rajani J.B., Treating Technologies of Shell Global Solutions for Natural Gas and Refinery Gas Streams, In "Research Institue of Petroleum Industry Congress", 12: 1-19 (2004).
[4] Papadopoulos, Michael N., Carl H. Deal. "Method of Separating Acidic Gases from Gaseous Mixtures", U.S. Patent 3,347,621, October 17 (1967).
[5] Ghanbarabadi H., Khoshandam B., Simulation and Comparison of Sulfinol Solvent Performance with Amine Solvents In Removing Sulfur Compounds and Acid Gases From Natural Sour Gas, Journal of Natural Gas Science and Engineering, 22: 415-420 (2015).
[7] Gouedard C., Picq D., Launay F., Carrette P.-L., Amine Degradation in CO2 Capture. I. A Review. International Journal of Greenhouse Gas Control, (10): 244-270 (2012).
[9] Dicko M., Coquelet C., Jarne C., Northrop S., Richon D., Acid Gases Partial Pressures Above a 50 wt% Aqueous Methyldiethanolamine Solution: Experimental Work and Modeling, Fluid Phase Equilibria, 289(2): 99-109 (2010).
[10] Shokouhi M., Ahmadi R., Measuring the Density and Viscosity of H2S-Loaded Aqueous Methyldiethanolamine Solution, The Journal of Chemical Thermodynamics, 102: 228-236 (2016).
[11] Shokouhi M., Jalili A.H., Zoghi A.T., Experimental Investigation of Hydrogen Sulfide Solubility in Aqueous Sulfolane Solution. The Journal of Chemical Thermodynamics, 106: 232-242 (2017).
[12] Kuranov G., Rumpf R., Smirnova N.A., Maurer G., Solubility of Single Gases Carbon Dioxide and Hydrogen Sulfide in Aqueous Solutions of N-Methyldiethanolamine in the Temperature Range 313− 413 K at Pressures up to 5 MPa, Industrial & Engineering Chemistry Research, 35(6): 1959-1966 (1996).
[13] Kamps P.-S.Á., Model for the Gibbs Excess Energy of Mixed-Solvent (Chemical-Reacting and Gas-containing) Electrolyte Systems, Industrial & Engineering Chemistry Research, 44(1): 201-225 (2005).
[14] Prausnitz J.N., Lichtenhaler R.N., Agevedo E.G., “Molecular Thermodynamics of Fluid Phase Equilibria”, 3th ed., Prentice-Hall, Englewood Cliffs, NJ, (1999).
[15] Aroua M.K., Salleh R.M., Solubility of CO2 in Aqueous Piperazine and Its Modeling Using the Kent‐Eisenberg Approach, Chemical Engineering & Technology: Industrial Chemistry‐Plant Equipment‐Process Engineering‐Biotechnology, 27(1): 65-70 (2004).
[16] Goncharov V.V., Verstakov E.S., Kessler Y.M., Dielectric and Viscous Properties of Water-Tetramethyl Sulfone Mixtures, J. Structure Chemistry, 24(6): 869-872 (1984).
[17] Saleh M.A., Ahmed M.S., Begum S.K., Density, Viscosity and Thermodynamic Activation for Viscous Flow of Water + Sulfolane. Physics and Chemistry of Liquids, 44(2): 153-165 (2006).
[18] Wang Y.‐W., Otto F.D., Mather A.E., Xu S., Solubilities and Diffusivities of N2O and CO2 in Aqueous Sulfolane Solutions, Journal of Chemical Technology & Biotechnology, 51(2): 197-208 (1991).
[19] Shokouhi M., Jalili A.H., Mohammadian A.H., Hosseini-Jenab M., Sadraei-Nouri S., Heat Capacity, Thermal Conductivity and Thermal Diffusivity of Aqueous Sulfolane Solutions, Thermochimica Acta, 560: 63-70 (2013).
[20] Shokouhi M., Jalili A.H., Zoghi A.T., Carbon Dioxide Solubility in Aqueous Sulfolane Solution, The Journal of Chemical Thermodynamics, 132: 62-72 (2019).
[21] Benoit R.L., Choux G., Réactions dans le Sulfolane. III. Etude des Interactions Eau–Sulfolane. Canadian Journal of Chemistry 46(20): 3215-3219 (1968).
[22] Dortmund Data Bank Software and Separation Technology
[24] Xu S., Qing S. Zhen Z., Zhang C., Carroll J.J., Vapor Pressure Measurements of Aqueous N-Methyldiethanolamine Solutions, Fluid Phase Equilibria, 67: 197-201 (1991).
[26] Chapoy A., Mohammadi A.H., Tohidi B., Experimental Measurement and Phase Behavior Modeling of Hydrogen Sulfide− Water Binary System, Industrial & Engineering Chemistry Research, 44(19): 7567-7574 (2005).
[27] Jalili A.H., Shokouhi M., Samani F., Hosseini-Jenab M., Measuring the Solubility of CO2 and H2S in sulfolane and the Density and Viscosity of Saturated Liquid Binary Mixtures of (Sulfolane + CO2) and (Sulfolane + H2S). The Journal of Chemical Thermodynamics, 85: 13-25 (2015).
[28] Roberts B.E., Mather A.E., Solubility of H2S and CO2 in Sulfolane. The Canadian Journal of Chemical Engineering, 66(3): 519-520 (1988).
[29] Murrieta-Guevara F., Romero-Martinez A., Trejo A., Solubilities of Carbon Dioxide and Hydrogen Sulfide in Propylene Carbonate, N-Methylpyrrolidone and Sulfolane, Fluid Phase Equilibria, 44(1): 105-115 (1988).
[30] Jou F-Y., Deshmukh, R.D., Otto, F.D., Mather A.E., Solubility of H2S, CO2, CH4 and C2H6 in Sulfolane at Elevated Pressures, Fluid Phase Equilibria, 56: 313-324 (1990).
[31] Macgregor R.J., Mather A.E., Equilibrium Solubility of H2S and CO2 and Their Mixtures in a Mixed Solvent, The Canadian Journal of Chemical Engineering, 69(6): 1357-1366 (1991).
[32] Sidi-Boumedine R., Horstmann S., Fischer K., Provost E., Fürst W., Gmehling J., Experimental Determination of Hydrogen Sulfide Solubility Data in Aqueous Alkanolamine Solutions, Fluid Phase Equilibria, 218(1): 149-155 (2004).
[33] Kamps P.-S., Balaban A., Jodecke M., Koranov J., Smirnova N.A., Maurer G., Solubility of Single Gases Carbon Dioxide and Hydrogen Sulfide in Aqueous Solutions of N-Methyldiethanolamine at Temperatures from 313 to 393 K and Pressures up to 7.6 MPa:  New Experimental Data and Model Extension, Industrial & Engineering Chemistry Research, 40(2): 696-706 (2001).
[34] Mathonat C., Majer V., Mather A.E., Grolier J.-P.E., Enthalpies of Absorption and Solubility of CO2 in Aqueous Solutions of Methyldiethanolamine, Fluid Phase Equilibria, 140(1-2): 171-182 (1997).