Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore.
J Chem Phys. 2011 Apr 7;134(13):134705. doi: 10.1063/1.3573902.
A molecular simulation study is reported for water desalination in zeolitic imidazolate framework-8 (ZIF-8) membrane. The simulation demonstrates that water desalination occurs under external pressure, and Na(+) and Cl(-) ions cannot transport across the membrane due to the sieving effect of small apertures in ZIF-8. The flux of water permeating the membrane scales linearly with the external pressure, and exhibits an Arrhenius-type relation with temperature (activation energy of 24.4 kJ∕mol). Compared with bulk phase, water molecules in ZIF-8 membrane are less hydrogen-bonded and the lifetime of hydrogen-bonding is considerably longer, as attributed to the surface interactions and geometrical confinement. This simulation study suggests that ZIF-8 might be potentially used as a reverse osmosis membrane for water purification.
本文对沸石咪唑酯骨架-8（ZIF-8）膜中的水脱盐进行了分子模拟研究。模拟表明，在外压作用下发生水脱盐，由于 ZIF-8 中小孔的筛分作用，Na(+)和 Cl(-)离子无法穿过膜。透过膜的水通量与外压呈线性关系，与温度呈阿累尼乌斯型关系（活化能为 24.4 kJ∕mol）。与体相相比，ZIF-8 膜中的水分子氢键较少，氢键的寿命明显更长，这归因于表面相互作用和几何约束。这项模拟研究表明，ZIF-8 可能有潜力用作反渗透膜来进行水净化。
