US 11,938,451 B2
Graphene-based membrane and method of preparation thereof
Slaven Garaj, Singapore (SG); and Seunghyun Hong, Singapore (SG)
Assigned to National University of Singapore, Singapore (SG)
Filed by National University of Singapore, Singapore (SG)
Filed on Apr. 21, 2020, as Appl. No. 16/854,176.
Application 16/854,176 is a division of application No. 15/360,543, filed on Nov. 23, 2016, abandoned.
Claims priority of provisional application 62/386,274, filed on Nov. 24, 2015.
Prior Publication US 2020/0276543 A1, Sep. 3, 2020
Int. Cl. B01D 71/02 (2006.01); B01D 67/00 (2006.01); B01D 69/02 (2006.01); B01D 69/10 (2006.01)
CPC B01D 71/021 (2013.01) [B01D 67/0041 (2013.01); B01D 69/02 (2013.01); B01D 69/10 (2013.01); B01D 2323/35 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method of separating hydrated ions from a fluid stream, the method comprising:
providing a plurality of graphene-based membranes, each graphene-based membrane comprising a stacked arrangement of layers of a graphene-based material, the layers of the graphene-based material defining one or more nanochannels between neighboring layers,
chemically engineering one or more of the plurality of graphene-based membranes to possess a desired electrical charge to increase a filtering efficiency for hydrated anions at substantially a same size of the one or more nanochannels for maintaining a desired flow though the graphene-based membrane,
chemically engineering one or more of the plurality of the graphene-based membranes to possess a desired electrical charge to increase a filtering efficiency for hydrated cations at substantially a same size of the one or more nanochannels for maintaining a desired flow though the graphene based membrane,
disposing the plurality of graphene-based membranes such that one or more adjacent cell pairs are provided, each cell pair comprising one graphene-based membrane for filtering the anions and one graphene-based membrane for filtering the cations separated by a passageway, and
directing a fluid stream comprising the hydrated ions through the respective passageways for filtering of the hydrated ions from the fluid stream.