Catalyst for air cleaning with synergistic effect
ARRS award for publication in 2021 – Excellence in science
Ljubljana, April 30, 2020 - Volatile organic compounds (VOCs), emitted mainly from industrial processes, transportation and consumer products, represent the main class of air pollutants with toxic and carcinogenic nature. In the achievement, we focused on a nowadays fast developing research area to manage VOC exhaust by treating industrial waste gases with catalysts. Monometallic (CuO and FeOx) and bimetallic (CuFeOx) entities on different porous supports are promising transition-metal low-cost catalysts for catalytic oxidation of VOC from industrial air alternatively to noble-metal catalysts which are currently in use.
In this work we report for the first time that the promotion of catalytic oxidation of toluene as a model VOC is due to the synergistic redox effect between CuO nanocrystals and finely dispersed Cu-oxo-Fe clusters on mesoporous silica with defined Fe/Cu molar ratio. This increases the number and reactivity of adsorbed electrophilic (O- and O2- ) as well as nucleophilic lattice oxygen (O2-) species at the CuO crystal and Cu-oxo-Fe cluster interface, thus providing up to twofold enhancement in catalytic activity for total oxidation of toluene. Fe on porous silicate support was synthesized via direct solvothermal synthesis followed by impregnation with Cu.
Environment-friendly and stable bimetal catalyst on porous support for total oxidation of VOC in industrial waste air was synthesized and its structure-property-performance relationship was determined. The results are an importand contribution to the research area of bimetal catalysts on porous supports with synergistics effect. Such catalysts can be used also in total oxidation of organic pollutants in wastewater or in selective oxidation in catalytic biomass conversion to chemicals or fuels.
Researchers of Department of Inorganic Chemistry and Technology (D09) Petar Djinović, Alenka Ristić, Tadej Žumbar, Nataša Zabukovec Logar and Nataša Novak Tušar with coauthors from the Department of Catalysis and Chemical Reaction Engineering (D13), Department of Materials Chemistry (D10) and Bulgaria (Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of science) published on the results of this research in the journal Applied Catalysis B Environmental (IF = 14.229).
Nataša Zabukovec Logar, coauthor and Head of Department of Inorganic Chemistry and technology (D09) at the National Institute of Chemistry in Slovenia commented: 'I am very glad that we succeeded to get an important new insight into operation of very topical supported bimetallic catalysts, which is an excellent basis for development of better and more efficient catalytic materials in the future.'
Gregor Anderluh, Director at National Institute of Chemistry in Slovenia commented: 'The research area of designing environmentally friendly and cost-effective advanced materials for VOCs is definitely a very important one. I am very proud of the achievement of our researchers since it has great potential to minimize the negative effects of industrial waste air.'
Krijn de Jong, Professor of inorganic chemistry at Utrecht University from the Netherlands commented: 'The authors took an original approach in studying synergy between supported metal oxide nanoparticles. For supported metal catalysts studies of bimetallic systems are common, but in supported metal oxides this is not the case. This research of Prof. Natasa Novak Tusar and co-workers stimulates us to think of supported multi-metal oxides for applications such as oxidation catalysis.'
Rafael Luque, Professor of Organic Chemistry at Cordoba University from Spain commented: 'This is a useful protocol that can pave the way to the design of environmentallly friendly and cost effective advanced functional materials for VOCs even at industrial premises, with relevant potential for future scaling up.'
Christian Hulteberg, Professor of Chemical Process Engineering at Lund University and the Director of Hulteberg Chemistry and Engineering company from Sweden commented: 'The inclusion of Cu-Fe-oxide clusters appears to provide a significant improvement in activity and better utilisation of CuO nanocrystals in the reduction of aromatic-type VOC compounds.However, scaling up to production is always easier on alumina than silica support.'
Nataša Novak Tušar, corresponding author, concluded: 'I am excited on these comments. We are just on the way to transfer knowledge on Cu and Fe functionalization of silica support to alumina support in the frame of doctoral thesis of coauthor Tadej Žumbar.'
DJINOVIĆ, Petar, RISTIĆ, Alenka, ŽUMBAR, Tadej, DASIREDDY, Venkata D. B. C., RANGUS, Mojca, DRAŽIĆ, Goran, POPOVA, Margarita, LIKOZAR, Blaž, ZABUKOVEC LOGAR, Nataša, NOVAK TUŠAR, Nataša. Synergistic effect of CuO nanocrystals and Cu-oxo-Fe clusters on silica support in promotion of total catalytic oxidation of toluene as a model volatile organic air pollutant., APPLIED CATALYSIS B: ENVIRONMENTAL, 2020, 268, 1-10.
For further information please contact: natasa.novak.tusar[at]ki.si