The Change Of Adsorption Properties Of
THE CHANGE OF ADSORPTION PROPERTIES OF
ZEOLITE-CONTAINING MICROSPHERES IN CONSEQUENCE
OF ACIDITY INOCULATION
L. Patrylak1, K. Patrylak1, R. Leboda2, J. Skubiszewska-Zięba2
1Institute of Bioorganic Chemistry and Petrochemistry of National Academy of Sciences of Ukraine; 1, Murmans’ka vul., Kyiv, 02094 Ukraine
2Department of Chemical Physics, Faculty of Chemistry,
Maria Curie-Sklodowska University; 20031 Lublin, Poland
To get the catalytic activity to the NaY-zeolite-containing microsphere (ZCMS) [1], i.e. to transform the last into catalyst, the ZCMS must be subjected to the surface acidity inoculation and thermal stabilization by rigid procedures of ion exchange in acid media (pH=3-4) and thermal treating at 550-560 0C [2]. Of course, under such hard conditions the treated material suffers great structural changes, which touch both matrix and zeolite phases.
This work describes the change of adsorption properties (all adsorption measurements were carried out using the low temperature nitrogen adsorption method) of the ZCMS when passing from the last to the catalyst on its basis (Table).
First of all, during such a transformation, BET and Langmuir surface areas, including micropore area, as well as the micropore volume, decrease essentially (positions 1, 2, 5, 
, whereas the BJH cumulative adsorption and desorption areas of pores between 17 and 3000 Е, in contrast, appreciably increase (positions 3, 4) which means, that the increase of mesopores and transport pores proceeds mainly on the account of the zeolite phase destroy. The scale of the last may be assess approximately as two-times one.
This destroy resulted in the average pore diameter (4V/A by Langmuir) half as much (approximately) increase (position 9). At the same time, the pore volume as well as the average pore diameter according to BJH adsorption and desorption (positions 6, 7, 10, 11) remind practically unchanged.
In spite of such a scale destroy, the characteristics of catalyst obtained are essentially superior to the respective characteristics of Grace/Davison Corporation catalyst imported in the former USSR.
Table. Adsorption Characteristics of Zeolite-Containing Microspheres, the Catalyst on their Basis, and an Industrial Catalyst
No.
Characteristic and its dimension
Sample
ZCMS
Catalyst
Grace/Davison Corporation
1
BET surface area, m2/g
498.7
308.5
55.3
2
Langmuir surface area, m2/g
620.3
386.3
69.0
3
BJH cumulative adsorption surface area of pores between 17 and 3000 Ǻ diameter, m2/g
176
204
18
4
BJH cumulative desorption surface area of pores between 17 and 3000 Ǻ diameter, m2/g
196
230
23
5
Micropore area, m2/g
359.0
143.6
37.6
6
BJH cumulative adsorption pore volume of pores between 17 and 3000 Ǻ diameter, cm3/g
0.322
0.366
0.050
7
BJH cumulative desorption pore volume of pores between 17 and 3000 Ǻ diameter, cm3/g
0.339
0.385
0.056
8
Micropore volume, cm3/g
0.158
0.063
0.017
9
Average pore diameter, Ǻ
29
41
34
10
BJH adsorption average diameter, Ǻ
73
72
110
11
BJH desorption average diameter, Ǻ
69
68
97
Thus, the dynamic of the changes, which accompany the ZCMS activation, represent in total an interesting and significant material for the catalyst development.
References
1. K.Patrylak, R.Leboda, J.Skubiszewska-Zięba, R.Likhnyovskyi, L.Patrylak, V.Vypyraylenko. Zeolite-Containing Microspheres on the Basis of Ukrainian Kaolin - their Adsorption and Catalytic Properties. 5th Ukr.-Pol. Symp. Theor. and Exper. Stud. Interfacial Phenom. and their Technol. Applic.
2. Patrylak L. Adsorpt. Sci. Technolog., 18 (5), (2000).
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