Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

For Clean Water

22.07.2008
Chlorine-tolerant membranes for desalination

One of the most pressing needs of our time is safe, sustainable access to fresh water. The dominant technology for desalination of water is membrane-based desalination, an energy-efficient, environmentally friendly process.

Scientists have now developed a new membrane material that, unlike current polyamide membranes, tolerates chlorinated water. A team headed by Ho Bum Park (University of Ulsan, South Korea), Benny D. Freeman (University of Texas at Austin, USA), and James E. McGrath (Virginia Polytechnic Institute, Blacksburg, USA) reported in the journal Angewandte Chemie on a membrane that is made of sulfonated copolymers.

Chlorine is the most commonly used biocide in water treatment because it is both inexpensive and very effective in small amounts. The disinfection of water headed into membrane-based desalination facilities is crucial to hinder the growth of biofilms, which reduce efficiency. Polyamide membranes do not tolerate chlorine. This means that the water must first be treated with chlorine, and then the chlorine must be removed before the water comes into contact with the membrane. Before being fed into the supply network, the water must be chlorinated again. This is a complex, costly procedure.

Membranes made of polysulfone, a sulfur-containing engineering thermoplastic, are being considered as an alternative. They are highly tolerant to chlorine. However, polysufones are hydrophobic and do not allow enough water to pass through them. By attaching additional charged sulfonic acid groups, the researchers hoped to make the polymer more water friendly without affecting its other valuable properties.

Whereas previous efforts focused on modification of the polysulfone after polymerization, the team now took a different route: the simultaneous polymerization of disulfonated monomers (a building block containing two hydrophilic sulfonic acid groups) and another type of monomer led to the formation of a copolymer. Undesired side-reactions, cross-linking or breaks in the polymer chains do not occur by this method. Most importantly, it is possible to precisely control how many water-friendly, charged sulfonic acid groups are in the polymer chain. This allows the targeted generation of chlorine-resistant membranes whose permeability for water and salts can be tailored to specific applications (e.g., nanofiltration, reverse osmosis).

Benny D. Freeman | Angewandte Chemie International
Further information:
http://www.engr.utexas.edu/

More articles from Ecology, The Environment and Conservation:

nachricht Surface clean-up technology won't solve ocean plastic problem
04.08.2020 | University of Exeter

nachricht Improving the monitoring of ship emissions
03.08.2020 | Carl von Ossietzky-Universität Oldenburg

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: ScanCut project completed: laser cutting enables more intricate plug connector designs

Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.

Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...

Im Focus: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Rare Earth Elements in Norwegian Fjords?

06.08.2020 | Earth Sciences

Anode material for safe batteries with a long cycle life

06.08.2020 | Power and Electrical Engineering

Turning carbon dioxide into liquid fuel

06.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>