Data on searching for synergy between alcohol and salt to produce more potent and environmentally benign gas hydrate inhibitors

Anton P Semenov; Rais I Mendgaziev; Vladimir A Istomin; Daria V Sergeeva; Vladimir A Vinokurov; Yinghua Gong; Tianduo Li; Andrey S Stoporev

doi:10.1016/j.dib.2024.110138

Data on searching for synergy between alcohol and salt to produce more potent and environmentally benign gas hydrate inhibitors

Data Brief. 2024 Feb 9:53:110138. doi: 10.1016/j.dib.2024.110138. eCollection 2024 Apr.

Authors

Anton P Semenov¹, Rais I Mendgaziev¹, Vladimir A Istomin^{1

2}, Daria V Sergeeva^{1

2}, Vladimir A Vinokurov¹, Yinghua Gong^{1

3}, Tianduo Li³, Andrey S Stoporev^{1

4}

Affiliations

¹ Gubkin University, Department of Physical and Colloid Chemistry, 65, Leninsky prospekt, Building 1, 119991 Moscow, Russian Federation.
² Skolkovo Institute of Science and Technology (Skoltech), Nobelya Str. 3, 121205 Moscow, Russian Federation.
³ Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, PR China.
⁴ Department of Petroleum Engineering, Kazan Federal University, Kremlevskaya str. 18, Kazan 420008, Russian Federation.

Abstract

In order to systematically study the synergistic effect of gas hydrate inhibition with mixtures of methanol (MeOH) and magnesium chloride (MgCl₂), the impact of these compounds on the thermodynamic stability of methane hydrate in the systems of CH₄-MeOH-H₂O, CH₄-MgCl₂-H₂O, and CH₄-MeOH-MgCl₂-H₂O was experimentally investigated. The pressure and temperature conditions of the three-phase vapor-aqueous solution-gas hydrate equilibrium were determined for these systems. The resulting dataset has 164 equilibrium points within the range of 234-289 K and 3-13 MPa. All equilibrium points were measured as the endpoint of methane hydrate dissociation during the heating stage. The phase boundaries of methane hydrate were identified for 8 systems with MeOH (up to 60 mass%), 5 MgCl₂ solutions (up to 26.7 mass%), and 14 mixtures of both inhibitors. Most equilibrium points were measured using a ramp heating technique (0.1 K/h) under isochoric conditions when the fluids were stirred at 600 rpm. It was found that even a 0.5 K/h heating rate for the CH₄-MgCl₂-H₂O system at low salt concentrations, along with all mixed aqueous solutions with methanol, gives results that do not differ from 0.1 K/h, considering the measurement uncertainties. Most measurements for the CH₄-MgCl₂-H₂O system at high salt content were acquired using a step heating technique. The coefficients of the empirical equations approximating the equilibrium points for each inhibitor concentration were defined. The change in the slope parameter of the empirical equation was analyzed as a function of inhibitor content. Correlations that accurately describe the thermodynamic inhibition effect of methane hydrate with methanol and magnesium chloride on a mass% and mol% scale were obtained. The freezing temperatures of single and mixed aqueous solutions of methanol and magnesium chloride were determined experimentally to confirm the thermodynamic consistency of the methane hydrate equilibrium data.

Keywords: Gas hydrates; Ice freezing point; Magnesium chloride; Methane; Methanol; Phase equilibria; Thermodynamic hydrate inhibitors.