Over 80 % of the worlds energy demands continue to be met with fossil fuels. The environmental problems associated with this, such as global warming, are well-known. The efficient supply of energy based on renewable resources is becoming more pressing.
Hydrogen technology, which involves the production of hydrogen from biomass for use in electricity production in fuel cells, is a very promising approach. In the journal Angewandte Chemie, researchers led by Matthias Beller at the Leibniz Institute for Catalysis in Rostock (Germany) have now introduced a new catalyst that allows for the use of bioalcohols for the production of hydrogen. Their novel process proceeds efficiently under particularly mild conditions.Ethanol and other alcohols do not willingly give up their hydrogen atoms; this type of reaction requires highly active catalysts. Previous catalytic processes require downright drastic reaction conditions: temperatures above 200 °C and the presence of strong bases. The Rostock researchers thus aimed to develop a catalyst that would also work efficiently at significantly milder temperatures.
Martin Nielson, working on Beller’s team thanks to an Alexander von Humboldt scholarship, has now been successful.
The new catalyst demonstrates previously unachievable high efficiency in the extraction of hydrogen from alcohols under mild reaction conditions. Says Beller, “This is the first catalytic system that is capable of obtaining hydrogen from readily available ethanol at temperatures under 100 °C without the use of bases or other additives.”
After initial successful tests with a relatively easily converted model alcohol (isopropanol), the researchers turned their attention to ethanol, also known as the “alcohol” in alcoholic beverages. Ethanol has taken on increasing importance as a renewable resource but is significantly harder to convert. “Even with ethanol, this new catalyst system demonstrated an unusually good conversion rate under milder conditions (60–80 °C),“ says Beller. “In comparison to previous catalyst systems, this one is nearly an order of magnitude higher.”
The active catalyst consists of a ruthenium complex that is formed in situ. The starting point is a central ruthenium atom that is surrounded by a special ligand that grasps it from three sides. The other ligands are a carbon monoxide molecule and two hydrogen atoms. Upon heating, a hydrogen molecule (H2) is released from the complex. When the remaining complex comes into contact with ethanol or isopropanol it grabs two replacement hydrogen atoms, allowing the cycle to begin again.Author: Matthias Beller, Leibniz-Institut für Katalyse an der Universität Rostock (Germany), http://www.catalysis.de/Beller-Matthias.239.0.html
Angewandte Chemie International Edition 2011, 50, No. 41, 9593–9597, Permalink to the article: http://dx.doi.org/10.1002/anie.201104722
Matthias Beller | Angewandte Chemie
Atomic-level motion may drive bacteria's ability to evade immune system defenses
24.04.2017 | Indiana University
Two-dimensional melting of hard spheres experimentally unravelled after 60 years
24.04.2017 | University of Oxford
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
24.04.2017 | Physics and Astronomy
24.04.2017 | Materials Sciences
24.04.2017 | Life Sciences