Breakthrough Environmental Nanotechnologies from Olomouc

Palacký University is among the leaders in European environmental research, due to the activities of the Regional Centre of Advanced Technologies and Materials (RCPTM), which participates in key projects in water treatment and soil remediation. The common denominator is nanomaterials, materials consisting of particles 100–1000 times smaller than the diameter of a human hair.

“We conduct both basic and applied research. Our approach is very complex and includes development of new nanomaterials, their optimisation and transfer to the production phase, and pilot testing at sites with a specific type of contamination,” said Jan Filip of the RCPTM.

Researchers are involved in a number of national projects, and co-ordinate the Czech national Competence Centre called Environmentally Friendly Nanotechnologies and Biotechnologies in Water and Soil Treatment.

“It is the most extensive Czech environmental project, supported by the Technology Agency of the Czech Republic, whose allocation amounts to almost €12 million. Apart from three academic institutions, six industrial companies are also involved, specialising in environmental remediation. Technologies developed in our Centre are commonly applied in practice,” said Radek Zbořil, the Director of the Competence Centre and General Director of the RCPTM.

Similar research is conducted within the Nanorem project, financed from the 7th Framework Programme of the European Union. This venture brings together 28 partners, mostly from European countries. The Olomouc team is in charge of the development of nanomaterials which are subsequently field-tested in a number of European sites in groundwater treatment.

Iron nanoparticles dominate

Olomouc researchers most often work with iron nanoparticles, which alter the physical and chemical parameters of groundwater and react with certain types of contaminating agents. They can break them down chemically or transform them from highly toxic forms into less toxic solid states.

With the help of nanotechnologies, Olomouc scientists are able to dispose of dozens of toxic substances from water, thus contributing to toxic waste disposal in sites where non-ecological plants operated in the past, or where former Soviet Army troops were stationed. The new technologies have proved their high efficacy in pilot remediation as well as in real-world practice. They facilitated decontamination of the premises of an industrial complex in Hořice, where the groundwater was contaminated with chlorinated hydrocarbons. On the premises of the Kara textile company in Trutnov, they contributed to treatment of groundwater contaminated with chromium(VI), used abundantly in the fur-making industry.

Can nanotechnologies deal with cyanobacteria?

According to scientists, iron nanoparticles might be used in decontamination of groundwater from cyanobacteria. Together with their colleagues from Brno, Olomouc scientists have been testing technologies efficiently eradicating these unwanted “water blooms”. “Materials based on iron can release phosphorus, which is the key nutrient for cyanobacteria. In addition, they degrade their cells and absorb the released toxins produced by these organisms,” explained Zbořil.

Nanotechnologies are relied upon also in the solution of one of the gravest ecological problems of today, which is the presence of arsenic in drinking water in many Asian countries, Europe, the United States, and South America. Arsenic contamination could be relatively easily removed by filters containing iron nanoparticles developed at the RCPTM.

Another possibility is using iron compounds in high oxidation states (ferrates). These are capable of superior elimination of arsenic and its firm chemical embedding in secondary formed iron oxides, thereby preventing its secondary release into the environment, which is the main drawback of current adsorption technologies. After the application of nano-iron, only non-toxic iron oxides remain in the water, similar to minerals naturally occurring in rocks and soils.

The Brno company Asio, in collaboration with Olomouc scientists, has developed reactors that could be used in water, along with ferrate application, for removal of arsenic or residues of pharmaceutical products, hormonal contraceptives, herbicides, heavy metals, and microorganisms.

“These materials are aimed at purification and disinfection of drinking, surface, and wastewater or soil. They also have a great potential for treatment of chemical and biological warfare agents. Our future research will test these materials for application in industrial accidents or toxic spillages. Ferrates have a very rapid effect,” explained Filip.

Where traditional methods fail

The potential of application of nanomaterials in water treatment is immense. “They are capable of eliminating contamination that cannot be removed by any other technology. Nanoparticles are conveyed to groundwater through a system of drills and then work independently. There’s no need to separate them and rinse huge quantities of soil or rocks, or draw the water to the ground and then treat it expensively,” clarified Filip.

In other projects, Olomouc experts are investigating the optimisation of materials currently used for water filtration. Their patented technology allows antimicrobial treatment of filters and membranes using nanosilver. Nanosilver is firmly embedded in the structure of the material, so it is not released into the environment. Such modified filters and membranes are more resistant to the development of biofilms, allowing their lifetime to be extended, which has a significant economic impact.

Researchers are not only investigating the processes of water and soil treatment, but are also considering the impact of new technologies on the environment. Their focus extends even to reaction products for application of new technologies.

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