Integration of graphene oxide in mixed-matrix membranes: balancing membrane performance with fouling resistance

Transcription

1 Integration of graphene oxide in mixed-matrix membranes: balancing membrane performance with fouling resistance Adam Inurria 1, Pinar Cay Durgun 2, Douglas Rice 1, Mary Laura Lind 2 François Perreault 1 1 School of Sustainable Engineering and the Built Environment 2 School for the Engineering of Matter, Transport and Energy Ira A. Fulton Schools of Engineering Arizona State University

2 Graphene-based materials Andre Geim and Konstantin Novoselov 2010 Nobel price in physics - Highest electron mobility - Highest thermal conductivity - High breaking strength - High optical transparency - Highest aspect ratio (2630 m 2 g -1 ) Geim and Novoselov. Nature Mater

3 Antimicrobial Properties of Graphene Perreault et al. Chem. Soc. Rev membrane puncturing Phospholipid extraction O 2 oxidation of cellular components Contact-mediated antimicrobial activity Does not deplete over time Does not release toxic compound

4 Membrane Biofouling Biofilm Membrane 1 µm Reduces permeate flux Reduces membrane selectivity Reduces membrane lifetime Up to 30% increase in operation costs Herzberg and Elimelech J. Membr. Sci.

5 GO Mixed Matrix Membranes Ctrl Estimate of new MMM Commercial Membranes Embedding graphene oxide sheets into the active layer of RO membranes can form nanochannels to enhance membrane performances. Yin et al. Desalination 2016, Mi Science 2014

6 Hypothesis and objectives Hypothesis: GO is a multifunctional nanomaterial that can impart antifouling properties and improve the membrane permselectivity Objective 1: Characterize the antimicrobial, anti-adhesive, and transport properties of GO mixed-matrix membranes of different GO loadings. Objective 2: Compare MMM with surface-functionalized membranes.

7 Graphene Oxide synthesis graphite Tour Tung Staudenmaier Hofmann graphite oxide ultrasonication graphene oxide Salt rejecting range Graphene Oxide Acid Oxidizing Agent Reducing Agent Tung H 2 SO 4 KMnO 4 - Tour 9:1 H 2 SO 4 : H 3 PO 4 KMnO 4 - Staudenmaier 9:1 H 2 SO 4 : 90% HNO 3 KClO 3 - Hofmann 9:1 H 2 SO 4 : 63% HNO 3 KClO 3 - rgo H 2 SO 4 KMnO 4 Hydrazine St Chng and Pumera Chem. Eur. J Mi. Science 2014 Inurria et al, in preparation

8 GO Mixed Matrix Membranes Polyamide MPD TMC 95 o C GO is added to the monomer solution before interfacial polymerization Inurria et al. In preparation Werber et al. Nature Materials 2015

9 Water permeance ( m s -1 MPa -1 ) Salt permeane ( m s -1 ) GO-MMM permselectivity Salt Rejection (%) * TFC TFN-7.5 TFN-15 TFN Limited improvement in membrane performance, and decreasing benefit as GO concentration increases Inurria et al. In preparation

10 Fluorescence intensity (a.u.) GO-MMM fouling with BSA-FITC a Blank TFC b b c 0 TFC TFN-7.5 TFN-15 TFN-22.5 TFN-7.5 TFN-15 TFN-22.5 Membrane fouling by proteins is also reduced when more GO is integrated into the MMM Inurria et al. In preparation

11 % of viable cells GO-MMM biocidal properties TFC TFN-low GO TFC-high GO 50 µm 50 µm 50 µm Increasing the concentration of GO in the MMM increases the antimicrobial properties of the membrane surface 0 TFC TFN-7.5 TFN-15 TFN-22.5 Inurria et al. In preparation

12 Two approaches for GO-enabled TFC Surface functionalization Mixed-Matrix Membranes Nanomaterials is grafted on the surface - Use small amount of NMs - Affect only surface properties - Less stable Nanomaterials is integrated into the polymer matrix - Provide stronger binding - Can affect transport properties - Use more NMs

13 Water Permeability, A (L m -2 h -1 bar -1 ) Salt Permeability, B (L m -1 h -1 ) Membrane Transport Properties A B Ctrl-TFC GO-TFC GO modification does not alter the membrane transport properties. Perreault et al., ES&T Lett. 2014

14 Antimicrobial Properties CFU (% of control) % inactivation after 1h of contact * 20 0 Ctrl-TFC GO-TFC Graphene oxide functionalized membranes inactivate E. coli cells attached to the membrane. Perreault et al., ES&T Lett. 2014

15 CFU (% of control) GO-MMM permselectivity % of viable cells Ctrl-TFC GO-TFC 0 TFC TFN-7.5 TFN-15 TFN-22.5 At similar antimicrobial effect, GO-MMM does not provide any improvement in membrane separation. GO-MMM uses more GO! GO-MMM cross-link the GO and reduce leaching.

16 Conclusions Antifouling properties increase with GO loading GO improves the membrane permeability at low loadings GO may be more performant as an antifouling agent than a permselectivity enhancer MMM and surface functionalization offer similar nano-enabled performance Are they equal in sustainability?

17 Acknowledgements

18 Acknowledgements Thank you!

19 Contact Angle ( ) Hydrophilic Surface Properties * Ctrl GO-TFC The hydrated layer of more hydrophilic surfaces can reduce the adhesion of foulants Perreault et al. ES&T 2016