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We use molecular dynamics (MD) simulations to examine the structural and dynamical properties of deep eutectic solvents (DESs)-based boron nitride nanotube (BNNT) nanofluid. The impacts of nanotube diameter on the physicochemical parameters of the systems under consideration are investigated. It is found that the addition of BNNT to DES increases viscosity as a result of a decrease in the diffusion coefficient of DES species. Similarly, increasing the diameter of the BNNT causes an increase in viscosity while reducing the diffusion coefficient of glycerol. The assessment of interaction energy and the number of hydrogen bonds rationalizes and explains these results. The density profile, radial distribution function, the number of hydrogen bonds, and orientation of two species are estimated to provide a molecular explanation of DES species behavior within and outside BNNTs. Our results reveal that the diameter of the BNNT influences the arrangement and number of DES species inside BNNTs. Except for the (8, 8) BNNT, where DES species are organized in a straight chain, the cylindrical structure of DES species is inferred inside all BNNTs. Likewise, various obtained physicochemical properties for glyceline are found in good agreement with experimental data. This new understanding of the DES-based nanofluids structure will help to understand the properties of these green novel solvents from the viewpoint of molecular scale in chemical processes, as well as suggest a powerful framework in solvent design applications.

Molecular dynamics simulations were performed to investigate the performance of three deep eutectic solvents (DESs) in the separation of acid gases from natural gas. To evaluate the efficiency of these DESs, their performance was compared with that of the conventional methyl diethanolamine (MDEA) system. For this purpose, the acidic DES (phenyl propionic acid and choline chloride; with 67 mol % Phpr), same acidic DES accompanied by boron-nitride nanotube (Nano-DES), and acidic DES with methyl diethanolamine (DES-MDEA) were considered. The solubility selectivity and diffusion selectivity were evaluated and compared to those of MDEA system. The Nano-DES system showed the best performance in terms of solubility selectivity of H2S over CH4, while the high solubility selectivity of CO2 over CH4 was obtained for pure DES systems. Likewise, the aqueous MDEA and the DES-MDEA systems exhibited the largest diffusivity selectivity of H2S over CH4 and CO2 over CH4, respectively. These results were rationalized and explained by analyzing the density profile and interaction energies. Besides, the radial and spatial distribution function, Gaussian normalized distribution of measured dipole moment of species, and the orientation of dipole moment species were investigated to explain the obtained results. Furthermore, dynamical properties such as mean square displacement and corrected diffusion coefficient of species indicated that CO2 molecules diffuse faster than H2S for studied systems except for aqueous MDEA. Likewise, the diffusion coefficient of H2S and CO2 in the considered systems follow the trends Nano-DES

The absorption of a Gaussian laser beam creates a temperature gradient. In this study, a surface tension gradient was created with a temperature gradient, and this surface tension gradient caused a mass transfer (Marangoni effect). The velocity and the director reorientation, which are the results of the Marangoni effect, were investigated. Both the change of velocity and the reorientation of the director in the r direction followed the gradient of the Gaussian profile of temperature. In addition, applying a magnetic field to the case was studied. The results were found to be in a range that can easily be checked experimentally.