It is also used to clean up nuclear waste. This extremely useful material is a zeolite. In its natural form it originates from volcanoes but it is synthesised for commercial purposes. A European team of scientists has revealed, for the first time, its chemical structure using the ESRF. This research, published in Nature Materials on 22 June, opens doors to more effective zeolites in the future.
Zeolites are crystalline white minerals, mostly made of aluminium, silicon and oxygen. Their structure is like molecular scaffolding, similar to a sieve. Thanks to this structure, they are frequently used as a “molecular sieve”. This means that with their pores they can separate different molecules and cause different reactions, which are crucial in treating petrol and producing chemicals. Zeolites can also provoke ion exchange, which is useful in water softening or in the removal of nuclear waste (by filtering the radioactive components).
Due to their importance in industry, there is extensive research on zeolites world-wide. However, a crucial aspect about these minerals is still not known. Their functioning and effectiveness depends on different parameters, such as the size of their pores and the distribution of aluminium in the structure of the zeolites. However, the location of the active aluminium remains unknown in many of these materials.
The team from the ETH Zurich, the European Synchrotron Radiation Facility (ESRF), Diamond Light source, the University of Torino and the University of Hamburg have determined unambiguously and directly the distribution of aluminium in zeolites using the technique of X-rays standing wave at the ESRF.
The object of the study was a scolecite zeolite, a natural mineral stemming from the zeolite-rich region of Puna in India. Natural zeolites are not so commonly used in industry because they tend to have more impurities than those synthesised, but they can be used in cleaning nuclear waste. After the Chernobyl catastrophe, tons of zeolites were used with the aim of cleaning the radioactively contaminated area.
The results from the experiments at the ESRF show optimism for the future of zeolites. “By being able to answer the question of where the active sites are, we open up the door to understanding the structure–performance relation. This will lead to ways of improving synthetic zeolites”, explains Jeroen van Bokhoven, corresponding author of the article in Nature Materials.
The next challenge for the team is to study synthetic zeolites with the same technique. Whilst natural zeolites, such as scolecite, contain crystals in the millimetre range, the synthetic ones tend to have much smaller grains, often not larger than a few micrometres. “We have also begun to investigate an industrial synthesised zeolite, but the study is as of yet not complete”, explains Joerg Zegenhagen, in charge of the ESRF beamline where experiments were carried out. “We are currently developing the different beamline elements so that in the very near future we can have the same exhaustive amount of information for synthetic zeolites as for scolecite”, he concludes.
*According to Material World, BBC4, 19 January 2006.
Montserrat Capellas | alfa
New concept for structural colors
18.05.2018 | Technische Universität Hamburg-Harburg
Saarbrücken mathematicians study the cooling of heavy plate from Dillingen
17.05.2018 | Universität des Saarlandes
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
22.05.2018 | Life Sciences
22.05.2018 | Earth Sciences
22.05.2018 | Trade Fair News