Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Alternative energy: A cooler way to clean hydrogen

25.06.2013
Converting bioethanol into hydrogen for fuel cells becomes significantly simpler with innovative metal catalysts

A process known as ethanol steam reforming is creating opportunities for fuel cell researchers, thanks to the recent rise of the bioethanol industry. This technique generates hydrogen gas (H2) directly within fuel cell systems onboard vehicles by decomposing bioethanol in the presence of special catalysts — an approach that could use current gasoline delivery infrastructures to power alternative energy transportation.

Currently, ethanol steam reforming suffers from a major obstacle: its multiple reaction pathways can produce toxic carbon monoxide (CO) byproducts that ruin fuel cell membranes.

Lin Huang, Jianyi Lin and co-workers from the A*STAR Institute of Chemical and Engineering Sciences in Singapore have now prepared a novel metal catalyst that can eradicate CO emissions from ethanol-derived H2 at temperatures 50 °C lower than previous catalysts1.

Low-temperature ethanol steam reforming boosts the safety and efficiency of fuel processing onboard vehicles, but requires a careful choice of catalysts. Rhodium (Rh), a relatively scarce transition metal, has gained attention among chemists because it targets ethanol’s carbon–carbon bond — the most difficult part of the alcohol to decompose. However, Rh catalysts tend to generate CO and methane byproducts when steam reforming conditions fall below 350 °C.

Huang, Lin and co-workers investigated whether they could resolve Rh’s shortcomings with cobalt (Co), a less expensive transition metal that has high selectivity toward H2 production at low temperatures. They explored whether Co could be combined with Rh on a nanostructured oxide surface to produce a dual-component catalyst. While making a mixed catalyst is relatively straightforward, finding one that maximizes the benefits of both metals for efficient steam reforming is not as easy. Therefore, the team investigated how different metallic precursors could achieve an ideal interaction between Rh and Co atoms on the supporting surface.

Their experiments revealed that catalysts consisting of Rh and Co, prepared from metal carbonyl precursors, gave high yields of extraordinarily clean H2 with no CO emissions at temperatures as low as 300 °C. According to Huang, these findings indicate that atomic interactions between the metals favor a particular pathway, known as the water–gas shift, which converts CO and water into H2 and carbon dioxide. However, mixed catalysts made from metal nitrate precursors failed to yield CO-free H2, presumably because of poor atomic interactions.

The team now faces two challenges: uncovering the mechanistic reasons why supported Rh–Co dual-component catalysts are so effective; and, reducing the build-up of carbonaceous coke deposits that adversely affect catalytic activity and stability during ethanol steam reforming.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Chemical and Engineering Sciences

Journal information
Huang, L., Choong, C., Chen, L., Wang, Z., Zhong, Z., Campos-Cuerva, C. & Lin, J. Monometallic carbonyl-derived CeO2-supported Rh and Co bicomponent catalysts for CO-free, high-yield H2 generation from low-temperature ethanol steam reforming. ChemCatChem 5, 220–234 (2013).

A*STAR Research | Research asia research news
Further information:
http://www.research.a-star.edu.sg/research/6692
http://www.researchsea.com

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>