2. ENVIRONMENTAL ChEMISTRy & TEChNOLOGy 2.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Environmental Chemistry & Technology
areas. The surface areas are relatively low because they were
measured only for comparison of the changes. These samples
were heated only at temperature 105 o C for two hours. In our
next study the surface area will be measured also after heating
at the higher temperatures up to 400 °C.
Fig. 1. Diagram of surface area changes Sa [m 2 g –1 ] of zeolitic
sample CT2, vs. its control (CTF): 1) starting sample, 2) three
months after the contamination by the Thiobacillus ferrooxidans
Fig. 2. Diagram of surface area changes Sa [m 2 g –1 ] of zeolitic
sample CuCT2, vs. its control (CTF): 1) starting sample, 2) one
year after the contamination by the Thiobacillus ferrooxidans
After the comparison of the samples before the contamination
by the microorganisms TF and the reference samples
CTF it was found out that even the nutrition medium itself,
pH = 1.57, contributes to the enlargement of the surface area.
The changes of the surface size and the pore volumes were
related also with the grain size. At the fine-grain fraction
CT-1 the enlargement of the surface of the reference sample
(CTF) was higher compared to the sample contaminated
by microorganisms. But at the coarse-grained fraction CT-2
which was contaminated by microorganisms the enlargement
of the surface area was higher compared with the reference
sample. However, more study is still necessary to confirm it
and to find out if a change of the grain-size has not occured
because such a change can cause an enlargement of the surface
size.
At the copper forms CuCT the activity of the microorganisms
caused enlargement of the surface area and the pore
s369
volumes at both the fine-grain and the coarse-grain fraction,
compared to the reference samples.
The copper forms were studied also with respect to a
copper bioleaching. According to the analyses of the copper
content in the samples contaminated by microorganisms for
one year their activity decreased the copper content about
60–75 % (e.g. Cu = 2.17 % in CuCT1 (0.1M) without TF;
Cu = 0.58 % in CuCT1 (0.1M) with TF after 1 year). The
bioleaching decreased the copper content in the copper forms
of the zeolitic samples (CuCT) depending on its starting concentration
and on other conditions of the bioleaching process.
Thiobacillus ferrooxidans utilises copper ions for its metabolic
processes. T. ferrooxidans contains in the periplasmic
space the small blue copper proteins – rusticyanin, which are
the principal component in the iron respiratory electron transport
chain 9 .
The study of the surface area changes and of the bioleaching
of copper continues with the aim to obtain more
detailed results after more time intervals and under various
conditions.
Conclusions
The results of the analyses of the surface area size and
the pores volume of the clinoptilolite and its copper forms
both before and after the contamination by microorganisms
Thiobacillus ferrooxidans confirmed the changes caused by
the presence of the microorganisms. The results of the copper
bioleaching too indicated that via the influence of the nutrition
media and metabolic activity of the microorganims there
occured changes of the zeolite surface and decrease of the
copper content in the samples. At the present we continue in
the study with the aim to obtain more experimental results
about the activity of the microorganisms acting for various
time intervals and at various conditions.
The combination of application of the zeolites and bioremediate
technologies, which use the metabolic activity
of the microorganisms looks to be a perspective ecological
alternation of the contaminants degradation.
This work has been supported by Scientific Grant
Agency of the Slovak Republic (grants No. 1/0107/08 and
2/7163/27).
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