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
Researchers target protein that protects bacteria's DNA 'recipes'
21.08.2018 | University of Rochester
Protein interaction helps Yersinia cause disease
21.08.2018 | Schwedischer Forschungsrat - The Swedish Research Council
There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.
The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
21.08.2018 | Ecology, The Environment and Conservation
21.08.2018 | Life Sciences
21.08.2018 | Power and Electrical Engineering