Surface Thermodynamics, Viscosity, Activation Energy of N-Methyldiethanolamine Aqueous Solutions Promoted by Tetramethylammonium Arginate

• Main Authors: Xiangfeng Tian, Lemeng Wang, Pan Zhang, Dong Fu
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Entropy
• Subjects: surface thermodynamics; viscosity; MDEA; [N₁₁₁₁][Arg]
• Online Access: https://www.mdpi.com/1099-4300/22/12/1337

The surface tension and viscosity values of N-methyldiethanolamine (MDEA) aqueous solutions promoted by tetramethylammonium arginate ([N₁₁₁₁][Arg]) were measured and modeled. The experimental temperatures were 303.2 to 323.2 K. The mass fractions of MDEA (<i>w</i>_MDEA) and [N₁₁₁₁][Arg] (<i>w</i>_[N1111][Arg]) were 0.300 to 0.500 and 0.025 to 0.075, respectively. The measured surface tension and viscosity values were satisfactorily fitted to thermodynamic models. With the aid of experimentally viscosity data, the activation energy (<i>E</i>a) and H₂S diffusion coefficient (<i>D</i>_H2S) of MDEA-[N₁₁₁₁][Arg] aqueous solution were deduced. The surface entropy and surface enthalpy of the solutions were calculated using the fitted model of the surface tension. The quantitative relationship between the calculated values (surface tension, surface entropy, surface enthalpy, viscosity, activation energy, and H₂S diffusion coefficient) and the operation conditions (mass fraction and temperature) was demonstrated.