Audio cassettes make the production process for fuels less expensive: To produce nanoparticles made of inexpensive iron oxide cores with a very thin cobalt shell, an international team of researchers modified a method developed for the production of magnetic audio tapes. As the researchers report in the journal Angewandte Chemie, their particles are easily accessible on a large scale, and are excellent Fischer–Tropsch catalysts for the production of good diesel fractions.
The increasing importance of shale gas and natural gas is bringing a century-old process back into the limelight: The Fischer–Tropsch synthesis, an industrial process for the liquefaction of coal developed in 1925, involves the catalytic conversion of a carbon monoxide/hydrogen mixture (synthesis gas) into gaseous and liquid hydrocarbons. These days, it is used in some countries for the production of ultrapure synthetic fuels from coal or natural gas. Biomass is also a good feedstock for this process.
The success of this process depends entirely on the catalyst, whose active component can be iron or cobalt. Each of these metals has advantages and disadvantages and one is chosen over the other based on the properties of the gas feed. Most large firms use cobalt, the major disadvantage of which is its price.
But, since only the surface of the catalytic particles is involved, one alternative is using particles with a core made of a less expensive material covered with a thin layer of the expensive, active material. However, this requires both nanometric accuracy and a cost-effective, simple, and scalable process for producing the catalytic particles, to ensure that they will still be cheaper than pure cobalt.
A Dutch, French, and German team led by Gadi Rothenberg at the University of Amsterdam together with Total Gaz & Energies Nouvelles (Paris) has now met this challenge by inventing new core–shell catalysts, inspired by patents from the 1960s for producing audio cassettes. The magnetic tapes used in these cassettes were coated with cigar-shaped iron oxide particles covered with a thin cobalt layer. By modifying this process, the researchers succeeded in making the spherical particles needed for catalysis.
The production process involves the synthesis of iron oxide nanoparticles from an iron chloride solution. Addition of a cobalt nitrate solution causes a thin layer of cobalt oxide to coat the nanoparticles. This allows the researchers to produce particles with a diameter of about 10 nm, consisting of an 8 nm iron oxide core and a whisper-thin, 1 nm cobalt-rich shell. These particles were processed with an alumina support to make pellets. To activate the catalyst, the pellets were heated under a hydrogen atmosphere, selectively reducing the cobalt oxide to metallic cobalt.
Tests in Fischer–Tropsch reactors at Lille and Bayreuth shows that the resulting particles are effective and robust catalysts. The product composition shows that the iron is also participating in the catalysis. There is clearly an iron–cobalt cooperative effect that has not been investigated before.About the Author
Author: Gadi Rothenberg, University of Amsterdam (The Netherlands), http://hims.uva.nl/research/research-groups/overview/overview/content/folder/heterogeneous-catalysis-and-sustainable-chemistry/people/people.htmlTitle: Design of Nanostructured Iron–Cobalt Fischer–Tropsch Catalysts
Gadi Rothenberg | Angewandte Chemie
Not of Divided Mind
19.01.2017 | Hertie-Institut für klinische Hirnforschung (HIH)
CRISPR meets single-cell sequencing in new screening method
19.01.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
19.01.2017 | Physics and Astronomy
19.01.2017 | Health and Medicine
19.01.2017 | Ecology, The Environment and Conservation