Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New process discovered: Mere sunlight can be used to eradicate pollutants in water

26.11.2018

Advances in environmental technology: You don’t need complex filters and laser systems to destroy persistent pollutants in water. Chemists at Martin Luther University Halle-Wittenberg (MLU) have developed a new process that works using mere sunlight. The process is so simple that it can even be conducted outdoors under the most basic conditions. The chemists present their research in the journal “Chemistry - a European Journal”.

The chemists at MLU rely on electrons moving freely in water, so-called hydrated electrons, to degrade dissolved pollutants.


The new process makes use of mere sunlight to destroy water pollutants.

Robert Naumann / Uni Halle

“These electrons are extremely reactive and can be used for a plethora of reactions. They break down even the most recalcitrant pollutants,” explains MLU-chemist Professor Martin Goez.

For this to work, however, the electrons have to be released from the molecular compounds in which they are usually tightly bound. Until now, generating those electrons has required complex and expensive high-power lasers.

Goez’s research group has been working for years on finding an alternative to this. A few months ago they introduced a new approach which only required a green light-emitting diode as the sole energy source. Vitamin C and traces of a metal complex as the catalyst were used to bring about the desired reaction.

However, the catalyst had to be enclosed in tiny containers known as micelles. This reduced the reaction’s efficiency, and the micelle molecules themselves were only partially biodegradable.

The group therefore looked for a way to avoid these additives. Ultimately, they found the answer in a highly charged anionic catalyst based on a ruthenium-metal complex.

By combining this with urate (a salt of uric acid), the researchers were able to effect the desired reaction in water without the need of micelles by exploiting the Coulombic repulsions.

Further investigations have revealed that the new process is not only a very efficient way to produce hydrated electrons but also has a wide range of applications.

“Our new approach is so simple that it doesn't even need to take place in a lab,” says Goez. His group conducted a field trial in a meadow and tested their new approach in water contaminated with chloroacetic acid. The result: the pollutants were eliminated in a small sample of water even when there was only a moderate amount of sunshine. Follow-up studies will examine whether the method developed by the chemists in Halle can also be used for large-scale removal of pollutants.

Originalpublikation:

Naumann R., Goez M., First Micelle-Free Photoredox Catalytic Access to Hydrated Electrons for Syntheses and Remediations with a Visible LED or even Sunlight, Chem. Eur. J., doi: 10.1002/chem.201803929

Tom Leonhardt | idw - Informationsdienst Wissenschaft
Further information:
http://www.uni-halle.de

More articles from Life Sciences:

nachricht An ion channel with a doorkeeper: The pH of calcium ions controls ion channel opening
25.06.2019 | Johannes Gutenberg-Universität Mainz

nachricht Symbiotic upcycling: Turning “low value” compounds into biomass
25.06.2019 | Max-Planck-Institut für Marine Mikrobiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fraunhofer IDMT demonstrates its method for acoustic quality inspection at »Sensor+Test 2019« in Nürnberg

From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.

Reducing machine downtime, manufacturing defects, and excessive scrap

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

For a better climate in the cities: Start-up develops maintenance-free, evergreen moss façades

25.06.2019 | Architecture and Construction

An ion channel with a doorkeeper: The pH of calcium ions controls ion channel opening

25.06.2019 | Life Sciences

Cooling with the sun

25.06.2019 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>