Separation performance of a binary organic mixture in a T-shaped carbon nanotube separator was firstly reported. One of the binary organic mixtures, difluoromethane/isobutane mixture, was selected as the studied mixture due to its great application potential as working fluid in thermodynamic cycles for efficient-utilization of low grade energy. Molecular dynamics simulation was utilized because of its advantages in revealing the molecular behavior and mechanism of the separation from the molecular interaction point of view. Both positive separation which driven by the external temperature difference, and passive separation resulting from the physical chemistry properties of the mixture were investigated. The potential of mean force and the interaction between the nanotube and the mixture molecules were utilized to analyze the underlying mechanism of the separation. The results indicate that a satisfactory separation performance can be obtained by the positive separation, and there's a remarkable separation. The asymmetric free energy change of each composition, and different interactions of the T-shaped carbon nanotube on the two types of molecules attribute to the separation. © 2020 Elsevier B.V.
Bibliographical noteThe work is supported by National Key Research and Development Program (Grant No. 2018YFB0905103), Tianjin Talent Development Special Support Program for High-Level Innovation and Entrepreneurship Team. In addition, the financial support from the China Scholarship Council (CSC, Grant no. 201906250021) to the first author is gratefully acknowledged.
- Carbon nanotube
- Molecular dynamics simulation
- Organic fluids
- Separation performance