Projects / Programmes
Development of photocatalytic superparamagnetic nanocomposites for application in diminishing emissions of harmful pollutants into an environment
Code |
Science |
Field |
Subfield |
2.04.01 |
Engineering sciences and technologies |
Materials science and technology |
Inorganic nonmetallic materials |
Code |
Science |
Field |
T153 |
Technological sciences |
Ceramic materials and powders |
decomposition of organic pollutants, magnetic nanoparticles, anatase, nanocomposite particles, photocatalysis
Researchers (10)
no. |
Code |
Name and surname |
Research area |
Role |
Period |
No. of publicationsNo. of publications |
1. |
07693 |
MSc Pavel Blagotinšek |
Chemical engineering |
Researcher |
2008 - 2011 |
22 |
2. |
27839 |
PhD Tanja Botić |
Systems and cybernetics |
Researcher |
2008 - 2011 |
73 |
3. |
26338 |
PhD Stanislav Čampelj |
Materials science and technology |
Junior researcher |
2008 - 2010 |
66 |
4. |
01360 |
PhD Mihael Drofenik |
Chemistry |
Researcher |
2008 - 2011 |
770 |
5. |
15148 |
PhD Darja Lisjak |
Materials science and technology |
Researcher |
2008 - 2011 |
422 |
6. |
10372 |
PhD Darko Makovec |
Materials science and technology |
Head |
2008 - 2011 |
673 |
7. |
07937 |
Andraž Molnar |
Chemical engineering |
Researcher |
2008 - 2011 |
0 |
8. |
29744 |
PhD Darinka Primc |
Materials science and technology |
Junior researcher |
2008 - 2011 |
44 |
9. |
14019 |
MSc Marjan Sajko |
Control and care of the environment |
Researcher |
2008 - 2011 |
142 |
10. |
08838 |
PhD Ernest Vončina |
Chemistry |
Researcher |
2008 - 2011 |
387 |
Organisations (3)
Abstract
An attractive solution of the problem related to the purification of the organic pollutants in wastewaters or gases involves their photocatalytic decomposition using titanium dioxide (TiO2) as a photocatalyst. For the photocatalytic purification a high surface area of the catalyst have to be available. The best solution is preparation of the photocatalyst in the form of nanoparticles and its dispersion in the polluted water. The problem with such a way of purification is in difficulty of the nanoparticles separation from the suspension, which can result in their unwanted emission into an environment. The problem of the nanoparticles emissions can be solved, if the photocatalytic nanoparticles are coated to the magnetic cores. Such magnetic photocatalytic particles can be separated from the suspension after purification using an external magnetic field. In the framework of this project the magnetic photocatalytic nanocomposite particles, composed of magnetic cores coated with photocatalytic TiO2 nanoparticles will be developed. Such photocatalytic particles will enable their dispersion in polluted water; their complete magnetic separation after purification and their recycling with re-dispersion in the new polluted water. They represent a new type of material, prepared with a method that can be relatively easily transferred into a mass production. Their preparation method base on the synthesis of photocatalytic nanoparticles using sulphate route or hydrothermal synthesis, followed by their coating to the surfaces of the pre-synthesized magnetic cores. The coating of the photocatalytic nanoparticles to the magnetic cores will take place in aqueous suspensions, while electric charge at the surfaces of the magnetic cores will be modify in such a way that they will attract the oppositely charged photocatalytic nanoparticles.
Significance for science
The topic of this project is the development of new, nanostructured particles for the photocatalytic decomposition of organic pollutants in water. The particles contain a surface coating of photocatalytic TiO2 nanoparticles and a superparamagnetic core (carrier), which enables their magnetic separation from the water suspension after the pollutant’s degradation.
The developed particles differ from those already described in the scientific literature in two ways:
(i) Magnetic carriers in the form of agglomerates composed of superparamagnetic nanoparticles were developed. Such magnetic carriers enable the effective separation of the photocatalyst from the suspension and their re-dispersion. Up to now, only photocatalytic composites with magnetic carriers comprising individual superparamagnetic nanoparticles or larger magnetic particles were presented. The disadvantage of the first is in the difficulty of their complete magnetic separation, and the disadvantage of the second is the difficulty of their re-dispersion after the magnetic separation.
(ii) Instead of the currently used sol-gel method, the hydrolysis of aqueous TiOSO4 was used for the synthesis of the anatase nanoparticles. The advantage of this process is its simplicity, which will facilitate its transfer to mass production.
Two methods for coating the photocatalyst onto the magnetic carriers were developed following two different approaches:
(i) Pre-synthesized anatase nanoparticles were combined with the magnetic agglomerates using hetero-agglomeration in the aqueous suspensions, applying electrostatic attractive forces between the particles with an opposite surface charge. Such an approach has been applied for the first time in development of this type of materials.
(ii) Magnetic agglomerates were coated with amorphous or nanocrystalline anatase TiO2 coatings using the hydrolysis of TiOSO4 in aqueous suspensions of the carriers. The method is general and can be used for the preparation of TiO2 coatings on different substrates. It can, therefore, be used for the development of different materials that are based on active TiO2 coatings, needed for different applications, such as in photovoltaics, nonlinear optics, for the preparation of antibacterial coatings, self-cleaning coatings, etc.
To achieve the goals of the project, the knowledge related to the synthesis of the anatase nanoparticles, of superparamagnetic iron-oxide (maghemite) nanoparticles, and to the control of their surface properties had to be expanded. Moreover, we had to expand our knowledge of the characterization of the materials’ photocatalytic activity and of related analytics.
Significance for the country
The topic of this project is the development of new, superparamagnetic photocatalytic particles for the oxidative decomposition of pollutants in water. Such particles will be dispersed in polluted water; their surface layer of TiO2 nanoparticles will provide photocatalytic activity in the decomposition of pollutants under UV irradiation, while their superparamagnetic cores will enable their magnetic separation after the treatment. While photocatalytic nanoparticles are already commercially available, the superparamagnetic photocatalytic particles represent a new product in the world market. All the developed technological processes involved in their production are appropriate for mass production. Further development of the methods, which will enable the production of larger amounts of the materials, is going on under financing of the industrial partner Cinkarna. The results of the project represent the foundations for the development of completely new products of high added value. Thus, the results will increase the competitiveness of Slovenian industry.
The project is also important for ecology. The pollution of water and air with organic pollutants is a very large problem also in Slovenia. The project will enable the development of entirely new approaches for the purification of polluted water and the preparation of drinking water. In the first place, the developed materials and the methods will be applied for the purification of large amounts of water polluted with low concentrations of organic pollutants.
The project is also important for the development of other products that are based on magnetic separation and on TiO2 coatings on different substrates. The knowledge needed for the coating of the TiO2 coatings on solid substrates was developed. The developed method was patented and will contribute to the further development of different TiO2 coatings needed in different areas, such us photovoltaics, self-cleaning and bactericide coatings, etc.
Four young researchers participated in the project. One of the project partners is the Faculty of Chemistry and Chemical Technology, University of Maribor. Thus, the project contributes to the improvement of the level of higher education and to better connections between industry, research and higher education in Slovenia.
Most important scientific results
Annual report
2008,
2009,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
2009,
final report,
complete report on dLib.si