Super mineral multifunctional

This material equals about 1 third of the average size of laundry detergent and helps refine 99% of gasoline worldwide. It is also used to clean up nuclear waste. The particularly useful material mentioned above is the Zeolite. In its natural form it originates from volcanoes but is synthesized for commercial purposes.

A group of European scientists first used ESRF to reveal its chemical structure. The study published in Nature Materials June 22 opens a new page for a more efficient generation of zeolites in the future.

Zeolites are white crystalline minerals, most of which are made of aluminum, silicon and oxygen. Its structure is a molecular mesh, like a sieve. Thanks to this structure, they are often used as 'molecular sieves'. That means that with holes in the structure, they can separate molecules and create different reactions.

It is therefore of decisive significance in the process of petroleum processing and chemical production. Zeolites are also capable of stimulating ion exchange, which is very useful in softening water or cleaning up nuclear waste (by filtering radioactive components).

The structure of scolecite zeolite, aluminum and silicon atoms are large spheres, connected by blue oxygen atoms.The openings in the structure are holes that carry molecules through the crystal to the active region.The plane where the dispersion in the standing X-ray wave test appears is marked;The experiment showed the distribution of aluminum and silicon in the crystal, giving a new understanding of the zeolite's active region.(Photo: J. Van Bokhoven)

Because they are of great importance in industry, there has been a lot of extensive research on zeolites worldwide. However, we have not found its decisive aspect. The performance and effectiveness of zeolite depend on different parameters, such as the size of the holes and the aluminum distribution in the structure of zeolite. However, the position of activated aluminum in the material has not been determined yet.

The research team of ETH Zurich, European Radon Radiation Facility (ESRF), Diamond Light, Torino University and Hamburg University have directly and clearly identified the distribution of aluminum in zeolites, using X-ray wave technique stands at ESRF.

The object of the study is scolecite zeolite , a natural mineral from a zeolite-rich region in Puna, India. Natural zeolites are often not used in industry because they contain more impurities than synthetic zeolites. However, they can be used in cleaning up nuclear waste. After the Chernobyl disaster, tons of zeolites were used for the purpose of cleaning up the radioactive contaminated area.

Results from experiments at the ESRF provide a prospect for the future of zeolites. Jeroen van Bokhovem, author of the article in Nature Materials, explains: 'Being able to answer the question of active site location, we opened the door to understanding the relationship between structure and ability. zeolite activity. This will bring about ways to improve synthetic zeolites'.

The next challenge for the group is to study zeolite synthesized with the above method. While natural zeolites, such as scolecite, contain crystals the size of millimeters; For synthetic zeolites, this size is much smaller, usually no bigger than a few micrometers.

Joerg Zegenhagen, in charge of ESRF beamline (molecular motion pathway through a linear accelerator) where experiments take place, explains: 'We have also begun to study industrial synthetic zeolites, but not yet completed. . We are developing beamline elements so that in the near future we can have a thorough amount of information about synthetic zeolites like scolecite '.