XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
342
T9: P–16
Comparison of theoretical and experimental studies of SCR deNO
x
over
Cu-USY structured catalyst
P. Jodłowski
1
, I. Czekaj
1
, Ł. Kuterasiński
2
, R.J. Jędrzejczyk
3
, D. Chlebda
4
, M. Sitarz
5
1
Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska
24, 31-155 Kraków, Poland, e-mail: jodlowski@chemia.pk.edu.pl
2
Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences,
Niezapominajek 8,30-239 Kraków, Poland
3
Malopolska Centre of Biotechnology, Gronostajowa 7A, 30-387 Kraków, Poland
4
Jagiellonian University, Faculty of Chemistry, Ingardena 3, 30-060 Kraków, Poland
5
Faculty of Materials Science and Ceramics, AGH University of Science and Technology,
Al. Mickiewicza 30, 30-059 Kraków, Poland
In this study we present theoretical and experimental results on mechanism of SCR deNOx
over Cu-USY structured catalyst prepared using sonochemical method. The aim of this research
was to correlate the information obtained from the DFT calculations with the in situ DRIFT and
UV-Vis experimental results. The Cu-USY zeolite was prepared by sonochemical method and
deposited on FeCralloy structured support. The prepared catalyst was examined several
characterization techniques including: μRaman, DRIFT and UV-Vis. Ab initio calculations
within the density functional theory are used implemented into StoBe software. The exchange
and correlation functional is approximated with a scalar relativistic spin paired Perdew-Burke-
Ernzerhof (PBE) formula. Cluster model of fujasite zeolite structure has been used and finally
the NO adsorption processes have been studied over Cu nanoparticles bound into zeolite
clusters. Several configurations, electronic structure (charges, bond orders) and density of states
have been analyzed to determine feasible pathways for the oxidation process. The NO reduction
cycles have been considered as a further step over Cu nanoparticles: i) at water deficient
conditions, ii) at water rich conditions. The comparison of the theoretical and experimental
studies allowed to propose mechanisms of deNOx under rich and lean reaction conditions.
Fig. 1. Cu-USY zeolite structure used during the modeling.
Keywords: methane combustion; in situ DRIFT; μRaman; reaction mechanism; wire gauze; cobalt oxide
Acknowledgment
Financial support for this work was provided by the National Centre for Research and Development
LIDER/204/L-6/14/ NCBR/2015 and partly within Polish National Science Centre – Project No.
2015/17/D/ST8/01252.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
343
T9: P–17
DFT modeling of lactic acid dehydration over Fe- and Sn- BEA zeolite
N. Sobuś
1
, I. Kurzydym
1
, and I. Czekaj
1
1
Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska
24, 31-155 Kraków, Poland, e-mail: iczekaj@chemia.pk.edu.pl
In the present study, we are interested in designing a new theoretical approach for the
synthesis of acrylic acid from lactic acid over zeolite catalysts. The theoretical modeling of
lactic acid dehydration would help in further development and synthesis of zeolite with declare
structure and obtain vibrational structure of substrates, products and intermediates. Lactic acid
adsorption and dehydration toward acrylic acid processes have been studied in BEA zeolite.
The electronic structure of all clusters was calculated by ab initio density functional theory
(DFT) methods (program StoBe) using the non-local generalized gradient corrected functionals
according to Perdew, Burke, and Ernzerhof (RPBE), in order to account for electron exchange
and correlation. A Al
2
Si
22
O
64
H
32
cluster was chosen to represent part of a single pore in the BEA
zeolite. The stabilization of monomeric and dimeric iron and tin complexes, such as M–OH,
HO–M–O–M–OH and M–O–M, in the BEA pore has been investigated
Possible modes of interaction of lactic acid with different cations (Si, Al, Fe or Sn) in BEA
zeolite framework as well as with added iron and tin nanoparticles have been considered. The
interactions of lactic acid is observed only above M–O–M dimmer The hydrogen abstraction
from methyl group over different oxygen and OH interactions with metallic sites of dimmer in
the zeolite framework have been observed, which succeed in acrylic acid formation (Fig. 1). The
vibrational structure of lactic and acrylic acid has been obtained, which could be compared with
experimental IR data.
Fig. 1. Scheme illustrating the lactic acid dehydration inside BEA zeolite.
Keywords: lactic acid; acrylic acid; DFT; vibrational structure; reaction mechanism; zeolites
Acknowledgment
This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under the Marie Skłodowska-Curie grant agreement No. 665778. (Polonez-1
2015/19/P/ST4/02482).
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