Polypiperazine-amide Nanofiltration Membrane Modified by Different Functionalized Multiwalled Carbon Nanotubes
Shuang-Mei Xue1, Zhen-Liang Xu1, Yong-Jian Tang1
1State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
ACS Applied Materials & Interfaces
|July 9, 2016
Summary
Modified carbon nanotubes enhance nanofiltration membranes. Hydroxyl-functionalized nanotubes (MWCNT-OH) improved water flux and salt rejection, showing potential for advanced separation technologies.
Area of Science:
- Materials Science
- Chemical Engineering
- Nanotechnology
Background:
- Nanocomposite membranes offer enhanced separation properties.
- Interfacial polymerization is a key technique for fabricating thin-film composite membranes.
- Surface functionalization of nanomaterials influences membrane performance.
Purpose of the Study:
- To investigate the effect of different functional groups on multiwalled carbon nanotubes (MWCNTs) on nanofiltration (NF) membrane performance.
- To fabricate and characterize MWCNT-based nanocomposite NF membranes.
- To evaluate the separation properties and stability of the modified membranes.
Main Methods:
- Fabrication of nanocomposite NF membranes via interfacial polymerization with piperazine (PIP) and functionalized MWCNTs (MWCNT-COOH, MWCNT-OH, MWCNT-NH).
- Characterization of MWCNTs using TEM, FT-IR, and TGA.
- Evaluation of membrane properties using XPS, TEM, AFM, contact angle measurements, and rejection tests.
Main Results:
- Successful incorporation of MWCNTs into the active layer of NF membranes was confirmed by XPS.
- Optimal separation properties were achieved at 0.01% (w/v) MWCNT concentration.
- The MWCNT-OH incorporated membrane exhibited the highest water flux (41.4 L·m⁻²·h⁻¹) and Na2SO4 rejection (97.6%).
- Increased hydrophilicity of functional groups led to variations in surface morphology, thickness, and hydrophilicity.
- All membranes showed a molecular weight cutoff (MWCO) below 300 Da and good operational stability.
Conclusions:
- Functional groups on MWCNTs significantly impact the performance of nanocomposite NF membranes.
- MWCNT-OH demonstrates superior performance in enhancing both water flux and salt rejection.
- The developed nanocomposite membranes show promise for efficient separation applications with good stability.
