Ronan Kelly
Retired 2020
Nanofilter to cut waterborne disease-related deaths
4 June 2013 By Tereza Pultarova
Indian scientists have developed a nanofilter to secure clean drinking water in the developing world
Indian scientists have come up with a new solution to secure safe drinking water for the developing world. The team, from the Indian Institute of Technology Madras (IITM), used a mixture of nanoparticles to form a 'nanocomposite' that releases a steady stream of silver ions that can rid drinking water of bacterial and viral contaminants.
The good news is that it seems to be largely affordable ? for just $2.50 a year, the technology promises to provide safe drinking water to families in remote rural areas. The estimated cost includes both, the cost of the device and the operating costs. The research results were published in May?s Proceedings of the National Academy of Sciences.
Although the technique was already known, the scientists had to identify the right material that would be both ? effective and affordable. "We had to find a material that was easily available, cheap, environmentally friendly and that maintained a sustained release of silver ions that could keep its concentration in water at less than 50 parts per billion, which is the WHO permissible level for silver [nanoparticles] in water", said Thalappil Pradeep, an author of the paper and a professor in IITM's chemistry department, in an interview with SciDev.Net.
...
http://eandt.theiet.org/news/2013/jun/nanofilter-waterborne-disease.cfm
vol. 110 no. 21 > Mohan Udhaya Sankar, 8459?8464
Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification
Mohan Udhaya Sankar1, Sahaja Aigal1, Shihabudheen M. Maliyekkal1, Amrita Chaudhary, Anshup, Avula Anil Kumar, Kamalesh Chaudhari, and Thalappil Pradeep2
Author Affiliations
Edited by Eric Hoek, University of California, Los Angeles, CA and accepted by the Editorial Board April 4, 2013 (received for review November 21, 2012)
Abstract
Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification.
hybrid green appropriate technology frugal science developing world
Footnotes
1M.U.S., S.A., and S.M.M. contributed equally to this work.
2To whom correspondence should be addressed. E-mail: pradeep@iitm.ac.in.
Author contributions: M.U.S., A.C., A., and T.P. designed research; M.U.S., S.A., S.M.M., A.C., A., A.A.K., and K.C. performed research; M.U.S., S.A., A., and T.P. analyzed data; and M.U.S., S.A., A.C., A., and T.P. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission. E.H. is a guest editor invited by the Editorial Board.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1220222110/-/DCSupplemental.
http://www.pnas.org/content/110/21/8459.abstract?sid=bde12b1e-65e9-4ebd-a995-e97d001bd430
4 June 2013 By Tereza Pultarova
Indian scientists have developed a nanofilter to secure clean drinking water in the developing world
Indian scientists have come up with a new solution to secure safe drinking water for the developing world. The team, from the Indian Institute of Technology Madras (IITM), used a mixture of nanoparticles to form a 'nanocomposite' that releases a steady stream of silver ions that can rid drinking water of bacterial and viral contaminants.
The good news is that it seems to be largely affordable ? for just $2.50 a year, the technology promises to provide safe drinking water to families in remote rural areas. The estimated cost includes both, the cost of the device and the operating costs. The research results were published in May?s Proceedings of the National Academy of Sciences.
Although the technique was already known, the scientists had to identify the right material that would be both ? effective and affordable. "We had to find a material that was easily available, cheap, environmentally friendly and that maintained a sustained release of silver ions that could keep its concentration in water at less than 50 parts per billion, which is the WHO permissible level for silver [nanoparticles] in water", said Thalappil Pradeep, an author of the paper and a professor in IITM's chemistry department, in an interview with SciDev.Net.
...
http://eandt.theiet.org/news/2013/jun/nanofilter-waterborne-disease.cfm
vol. 110 no. 21 > Mohan Udhaya Sankar, 8459?8464
Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification
Mohan Udhaya Sankar1, Sahaja Aigal1, Shihabudheen M. Maliyekkal1, Amrita Chaudhary, Anshup, Avula Anil Kumar, Kamalesh Chaudhari, and Thalappil Pradeep2
Author Affiliations
Edited by Eric Hoek, University of California, Los Angeles, CA and accepted by the Editorial Board April 4, 2013 (received for review November 21, 2012)
Abstract
Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification.
hybrid green appropriate technology frugal science developing world
Footnotes
1M.U.S., S.A., and S.M.M. contributed equally to this work.
2To whom correspondence should be addressed. E-mail: pradeep@iitm.ac.in.
Author contributions: M.U.S., A.C., A., and T.P. designed research; M.U.S., S.A., S.M.M., A.C., A., A.A.K., and K.C. performed research; M.U.S., S.A., A., and T.P. analyzed data; and M.U.S., S.A., A.C., A., and T.P. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission. E.H. is a guest editor invited by the Editorial Board.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1220222110/-/DCSupplemental.
http://www.pnas.org/content/110/21/8459.abstract?sid=bde12b1e-65e9-4ebd-a995-e97d001bd430