Tunable water desalination across Graphene Oxide Framework membranes

Journal Article · Wed Jan 01 04:00:00 EST 2014 · Physical Chemistry Chemical Physics. PCCP (Print)

DOI:https://doi.org/10.1039/c4cp01051e· OSTI ID:1127385

Nicolai, Adrien ^[1]; Sumpter, Bobby G ^[2]; Meunier, V. ^[1]

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1. Rensselaer Polytechnic Institute (RPI)
2. ORNL

The performance of graphene oxide framework (GOF) membranes for water desalination is assessed using classical molecular dynamics (MD) simulations. The coupling between water permeability and salt rejection GOF membranes is studied as a function of linker concentration n, thickness h and applied pressure DP. The simulations reveal that water permeability in GOF-(n,h) membranes can be tuned from 5 (n = 32 and h = 6.5 nm) to 400 L/cm2/day/MPa (n = 64 and h = 2.5 nm) and follows the law Cnh an . For a given pore size (n = 16 or 32), water permeability of GOF membranes increases when the pore spacing decreases, whereas for a given pore spacing (n = 32 or 64), water permeability increases by up to two orders of magnitude when the pore size increases. Furthermore, for linker concentrations n 32, the high water permeability corresponds to a 100% salt rejection, elevating this type of GOF membrane as an ideal candidate for water desalination. Compared to experimental performance of reverse osmosis membranes, our calculations suggest that under the same conditions of applied pressure and characteristics of membranes (DP 10 MPa and h 100 nm), one can expect a perfect salt rejection coupled to a water permeability two orders of magnitude higher than existing technologies, i.e., from a few cL/cm2/day/MPa to a few L/cm2/day/MPa.

• Research Organization: Oak Ridge National Laboratory (ORNL); Center for Nanophase Materials Sciences (CNMS); Oak Ridge Leadership Computing Facility (OLCF)
• Sponsoring Organization: DOE Office of Science; SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1127385
• Journal Information: Physical Chemistry Chemical Physics. PCCP (Print), Journal Name: Physical Chemistry Chemical Physics. PCCP (Print) Journal Issue: 18 Vol. 6; ISSN 1463-9076
• Country of Publication: United States
• Language: English