Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Uncovering a reaction’s secrets

23.03.2015

A theoretical and experimental study could lead to improved catalysts for producing hydrogen fuel from waste biomass

Experimental analysis and computer simulations reveal new insights into the process by which ethanol produced from waste biomass can be converted into hydrogen in the presence of a catalyst. These insights should aid the design of more efficient catalysts for hydrogen production.


Understanding the ethanol steam reforming reaction mechanism is crucial for the design of cheap and efficient catalysts able to convert biomass to hydrogen fuel.

© pitnu/iStock/Thinkstock

Hydrogen gas is an environmentally friendly alternative to fossil fuels. Today, through a process known as steam reforming, hydrogen is obtained by using steam to break up a hydrocarbon — most commonly, methane in natural gas. However, ethanol produced by fermenting waste biomass is potentially a cleaner starting material for this process.

However, despite having been extensively studied in recent years, steam reforming of ethanol is currently too inefficient to produce hydrogen on an industrial scale. This stems partly from the complexity of its reaction, which can yield a range of different products. “Our lack of understanding of the detailed reaction mechanism hinders further improvement of a catalyst for the reaction,” explains Jia Zhang of the A*STAR Institute of High Performance Computing in Singapore. “The reaction was a black box before we started exploring it.”

Now, Zhang and her co-workers have used experiments and computer simulations to probe how ethanol breaks down into hydrogen on rhodium catalysts supported on zirconia-based oxides1. These nanosized catalysts had previously been shown to be highly active for this reaction.

The team used gas chromatography and mass spectrometry to monitor in real time the intermediate species that form as the reaction proceeds. These measurements revealed that the C2H4O species is an important intermediate. Of the two possible structures this species can adopt, acetaldehyde (CH3CHO) was identified as the most probable one by the team’s computer calculations. The calculations also showed that water plays an unexpectedly important role in controlling the reaction pathway.

Based on this knowledge, the team proposed a mechanism for the reaction under their chosen conditions. Hydrogen is produced at most stages along the pathway, including the final step in which carbon monoxide reacts with water to produce hydrogen and carbon dioxide. The team’s calculations showed that the success of this final step is critical in determining the amount of hydrogen produced by steam reforming.

“Our theoretical simulations and experimental analysis provide important information on the reaction mechanism,” says Zhang. “This is a fundamental step forward in our understanding of the catalyst, which is the basis of catalyst design.” The team’s ultimate goal is to design catalysts that can produce hydrogen more cheaply and efficiently than current catalysts.

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

Reference
Zhang, J., Zhong, Z., Cao, X.-M., Hu, P., Sullivan, M. B. & Chen, L. Ethanol steam reforming on Rh catalysts: Theoretical and experimental understanding. ACS Catalysis 4, 448–456 (2014). | article

A*STAR Research | ResearchSEA
Further information:
http://www.research.a-star.edu.sg/research/7208
http://www.researchsea.com

More articles from Life Sciences:

nachricht The secret sulfate code that lets the bad Tau in
16.07.2018 | American Society for Biochemistry and Molecular Biology

nachricht Colorectal cancer risk factors decrypted
16.07.2018 | Max-Planck-Institut für Stoffwechselforschung

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

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication

16.07.2018 | Physics and Astronomy

New players, standardization and digitalization for more rail freight transport

16.07.2018 | Transportation and Logistics

Researchers discover natural product that could lead to new class of commercial herbicide

16.07.2018 | Agricultural and Forestry Science

VideoLinks
Science & Research
Overview of more VideoLinks >>>