XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
178
T1: P–45
Technological examination of XVI-th century religious panel paintings
Anna Klimek
1
, Karolina Budkowska
1
, Julio del Hoyo-Meléndez
1
,
Piotr Frączek
1
, and Michał Obarzanowski
1
1
National Museum in Krakow, Laboratory of Analysis and Nondestructive Investigation of Heritage
Objects, National Centre for Cultural Heritage Science, ul. Piłsudskiego 14, 31-109 Kraków, Poland,
e-mail: aklimek@muzeum.krakow.pl
The aim of this project was to examine painting materials in five Renaissance panel
paintings. Understanding the artists’ materials and techniques is one of the most important and
frequent requests posed by conservators and art historians. Scientific research can help in
planning and implementing a conservation treatment or dating of works of art based on specific
information such as pigment composition and their availability and chronology. The objects
investigated within the current study belong to the collection of the Castle Museum in Pszczyna.
Scientific imaging was conducted using different electromagnetic radiation ranges (VIS, UV,
IR) as well as digital X-ray radiography, to determine the overall state of preservation and to
obtain information on the overpaintings and paint loss. These images provide accurate
information about the surface and subsurface of the objects allowing an accurate selection of
measurement areas to be studied by physico-chemical methods. The next step was to determine
the elemental composition of paint layers by nondestructive X-ray fluorescence (XRF) analysis
in order to obtain information about the pigments used by the artists. Attenuated Total
Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) was applied for studying and
identifying binding media. Additionally, the morphology and composition were examined by
means of cross-sections prepared from microsamples extracted from the paintings using
scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDS). The
complementary information obtained through the use of the aforementioned techniques has
permitted to acquire a comprehensive knowledge about the composition and structure of this
important collection.
Keywords: conservation science; artists’ materials; FTIR
Acknowledgment
The research has been carried out within the project National Centre for Cultural Heritage Science co-
funded by the Polish Ministry of Culture and National Heritage. The project is implemented by the National
Museum in Krakow in collaboration with National Institute for Museums and Public Collections. The
objects under examination belong to collection of the Castle Museum in Pszczyna.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
179
T1: P–46
Tracking the ethanol transformation process over 10-MR zeolites using
Two Dimensional Correlation Spectroscopy (2D COS)
Kinga Gołąbek
1
, Karolina A. Tarach
1
, and Kinga Góra-Marek
1
1
Faculty of Chemistry, Jagiellonian University in Krakow, 3 Ingardena St., Krakow, Poland
e-mail: kmgolabek@gmail.com
The catalytic ethanol dehydration is a valuable source of diethyl ether (DEE), ethylene (C
2=
) and
higher hydrocarbons (C
3+
). DEE is considered as an industrially important reagent used as a solvent
and as a substrate for the synthesis of higher ethers. Ethene is an important petrochemical
intermediate for the production of e.g. polyethene and when produced from bioethanol assures
economic feasibility with higher purity.
In this work the role of pore arrangement of 10-MR zeolites: ZSM-5, TNU-9 and IM-5 as well as
their catalytic properties in ethanol transformation were investigated. Among all the studied catalysts,
the zeolite IM-5, characterized by limited 3-dimendionality, presented the highest conversion of
ethanol and the highest yields of diethyl ether (DEE) and ethylene. The less active and selective was
zeolite TNU-9 with the largest cavities formed on the intersection of 10-MR channels. This property
of TNU-9 can find the reflection in the mechanism of the DEE and ethylene formation. Analysis of
the ethanol transformation products and intermediate species was based on two-dimensional
correlation spectroscopy. Interaction of ethanol molecules with the Brønsted sites (Si(OH)Al) leads to
the formation of ethoxy species and water molecules in all the studied zeolites. In the synchronous
map the positive correlation between the 1450 and 1390 cm
–1
bands attributed to ethoxy species and
the 1625 cm
–1
band originated from water molecule is accompanied by the negative correlation within
the ethoxy species and ethanol bands. In whole temperature range, the most differentiated correlations
within the IR bands of high correlation level are observed for IM-5, in line with the privileged
transformation of ethanol over this zeolite at lower temperatures. When considering the synchronous
maps for the frequency region of 2900–3300 cm
–1
the formation of ether and ethene was also
evidenced.
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
0
2 0
4 0
6 0
8 0
1 0 0
Tem p er atu re [
o
C ]
D
E
E
Y
ie
l
d
[
%
]
TNU-9
IM -5
ZS M -5
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
0
2 0
4 0
6 0
8 0
1 0 0
Te mp er atu re [
o
C ]
C
o
n
v
e
rs
io
n
E
tO
H
[
%
]
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
0
2 0
4 0
6 0
8 0
1 0 0
Te mp er at ur e [
o
C ]
S
e
l
e
c
t
iv
it
y
to
e
t
h
e
n
e
[%
]
Fig. 1. Conversion of ethylene and DEE and C2= yield and selectivity to ethylene.
These catalysts have very similar channel dimensions, whereas the channel intersections give
raise to a variety of volumes in which reaction proceed. In TNU-9 possesses the largest cavity. In
ZSM-5 all intersections are equivalent, while IM-5 has three types of internal cavities. In the largest
cavity a side-pockets are present thus the higher activity of IM-5 can be considered in the terms of the
confinement effect.
Keywords: ethanol dehydration; zeolite; IR Spectroscopy; 2D COS
Acknowledgment
This work was financed by Grant No. 2015/18/E/ST4/00191 from the National Science Centre, Poland
References
[1] I. Noda, Appl. Spectrosc. 47 (1993) 1329.
[2] M. Choi, K. Na, J. Kim, Y. Sakamoto, O. Terasaki, R. Ryoo, Nature 461 (2009) 246.
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