Carbon nanotube membranes for desalination and water purification: Challenges and opportunities

doi:10.1016/j.nantod.2012.09.002

Nano Today

Volume 7, Issue 5, October 2012, Pages 385-389

https://doi.org/10.1016/j.nantod.2012.09.002 Get rights and content

Summary

The importance as well as impact of application of carbon nanotube (CNT) membranes in the area of water technology development is tremendous. A substantial amount of work have been carried out with impregnation of CNTs (simply as one of the reinforcements for incorporation of better properties like antibiofouling and/or better strength, etc.) in polymer host matrix. However, the volume of work enabling CNTs as flow channels (in a membranous structure) is not significant and that is where the potential benefits of CNTs lie. Moreover, from impressive works carried out in this direction, it is quite obvious that still significant challenges have to be addressed to align the CNTs, to reinforce it in a suitable host matrix without disturbing the alignment and inhibiting the agglomeration (adoption of suitable nanocomposite fabrication route), to open the tips preferentially and to scale up favorably. It is believed that the innovative attributes put forth by CNTs and the application areas identified with CNTs are getting matured, while the area of development of CNT (based) membranes is far from being matured and it still needs to be looked into in the light of involvement of materials as well as process challenges.

Graphical abstract

A schematic of CNT based water filter with aligned CNTs across the cylindrical geometry.

Highlights

► Importance of accessibility to safe drinking water by a common man is highlighted. ► Need for development of newer water technologies involving nanomaterials is emphasized. ► Opportunities and challenges involved in development of CNT based membrane are reported. ► Requirements that a CNT based membrane should fulfill to enable desalination and water purification are proposed.

Section snippets

Acknowledgements

We thank Mr. R.S. Tidke, Draftman, Desalination Division for preparing the schematic of CNT based nanocomposite membrane fabrication steps and Mr. Avishek Pal, Senior Research Fellow, Desalination Division for providing sincere technical suggestions on potential application of CNT based membranes in nanofiltration domain.

Soumitra Kar is a Young Scientist working in the Desalination Division of BARC. He is associated with the development of inorganic and organic membranes and membrane-assisted physicochemical processes for gas separation, water purification and effluent treatment. He is also actively involved in the development of carbon nanotube-based separation systems. He is a Life Member of American Nano Society and the Indian Desalination Association.

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R.C. Bindal is a Senior Scientist in the Desalination Division of BARC. He has been associated with the development of different types of membranes and membrane-based water purification devices. He is instrumental in developing five different water purification/industrial effluent treatment technologies including the technologies for microorganism, fluoride and arsenic decontamination. Currently his area of interest includes development of inorganic and mixed matrix nanocomposite membranes for radioactive waste treatment and gas permeation studies. He is member of several professional bodies associated with water technologies.

P.K. Tewari is a Outstanding Scientist and working as Head, Desalination Division, BARC and Professor in Homi Bhabha National Institute. He is the President of the Indian Desalination Association and sits on the Board of Directors of the International Desalination Association. He is the Chairman of the International Nuclear Desalination Advisory Group (INDAG) of the International Atomic Energy Agency (IAEA). He has been involved in providing consultancy services to several organisations on desalination and water purification. He is the Co-Chairman of the Editorial and Scientific Committee of the International Journal of Nuclear Desalination, member of the Editorial Board of Desalination and water Treatment Science and Engineering and Editor in-chief of International Journal of Nuclear Hydrogen Production and Applications.

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News and opinionsCarbon nanotube membranes for desalination and water purification: Challenges and opportunities

Summary

Graphical abstract

Highlights

Section snippets

Acknowledgements

Mater. Sci. Eng. B

Mater. Lett

Water Res.

Nano Today

J. Membr. Sci.

Nature

Langmuir

Science

Science

J. Am. Chem. Soc.

Int. J. Nucl. Desalination

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Carbon nanotube membranes for desalination and water purification: Challenges and opportunities