Understanding the water permeability and Cu2+ removal capability of two-dimensional nanoporous boron nitride

• Published in: Computational materials science Vol. 184; p. 109923
• Main Authors: Du, Jianbin, Feng, Zhifang, Han, Lijun, Ma, Xiangyun, Li, Qifeng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2020
• Subjects: Cu2+ removal; Hexagonal boron nitride (h-BN); Hydration radius; Molecular dynamics; Potential barrier; Molecular dynamics; Hexagonal boron nitride (h-BN); Potential barrier; Cu2+ removal; Hydration radius
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2020.109923

[Display omitted] •The h-BN nanosheet removed hazardous Cu2+ from industrial wastewater.•The potential barrier of membrane and Cu2+ was beneficial to the separation of Cu2+.•The second hydration radius of Cu2+ was calculated to explain the transport of Cu2+.•The energy consumption of h-BN removing Cu2+ was low. The discharge of Cu2+ from industrial wastewater to nature will pose a serious threat to human health. In order to separate Cu2+ from sewage, the copper removal process with hexagonal boron nitride (h-BN) membrane is studied using molecular dynamics simulations. The relationship between water flux and pore size, pore chemistry and external pressure is analyzed in detail, and the filtration mechanism of Cu2+ is also discussed. The results show that water flux is proportional to the pore size and external pressure. The water flux across the membrane with N-edged pore is larger. There is a potential barrier for Cu2+ with the membrane of B-edged pore, which is beneficial to the separation of Cu2+. When the radius of the pore is smaller than the second hydration radius of Cu2+, Cu2+ removal capability is better. In particular, nanoporous h-BN membrane with B5 pores has several orders of magnitude higher water permeability and 1–2 orders of magnitude lower energy consumption than traditional reverse osmosis membranes. Overall, this work has a guiding role in the liquid phase separation of heavy metal ions.