Mioara Zagrai


28-73 ÎNGLOBAREA DEŞEURILOR PE BAZĂ DE PLUMB ÎN STICLE TELURATE

THE INTEGRATED OF THE LEAD WASTES
IN TELLURATE GLASSES
In this work, we report structural investigations on vanadate-tellurate and borate-tellurate glasses system doped with lead oxide obtained by melt quenching method. The purpose of this paper was i) to integrate of the lead ions in these glasses and ii) to investigate of the structural properties of the obtained glasses in order to possible applications in the wastes recycling.
FTIR spectra analysis suggests that the lead oxide generates the rapidly deformation of the Te-O-Te linkages from [TeO4] structural units. Further the excess of oxygen ions can be accommodated in the host matrix by conversion of some [VO4] structural units into pyro vanadate units. Then, the increase of the lead oxide in the borate-tellurate matrix will produce the intercalation of [PbOn] entities where n=3 and 4.
Based on FTIR results, we found that the increase of the lead oxide in the borate-tellurate network suggests a gradual inclusion of these ions in the host matrix by the intercalation of [PbOn] structural units.
Keywords: bottles of lead telluride-based, IR, recycling
Cuvinte cheie: sticle telurate pe bază de plumb, spectroscopie IR, reciclare

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26-28 IMOBILIZAREA UNOR DEŞEURI RADIOACTIVE ÎN SISTEME VITROASE PE BAZĂ DE PLUMB

IMOBILIZATION OF THE RADIOACTIVE WASTES
IN VITREOUS SYSTEMS ON THE BASED OF LEAD
Immobilization of radioactive wastes by the vitrification method is a
well-established process that was selected because glass is highly stable, very
durable and has the ability to incorporate a wide variety of chemical
contaminants. In this work, we propose a study of the structural and behaviour
properties of lead glasses with xGd2O3∙(100-x)[4PbO2∙Pb] composition where
x=0-50%mol Gd2O3 in view of the possible applications as alternative of
immobilization of the radioactive wastes.
One of the most important requirements for the technology used in the
immobilization of nuclear wastes is to include as much as possible waste per
unit mass of the host vitreous matrix. We were synthesized the gadolinium-lead
glasses up to 50% mole Gd2O3. EPR data suggest that the gadolinium ions at
high contents have a behaviour of network former and not network modifier.
Keywords: bottles, Gadolinium-based lead, IR spectroscopy and RES,
waste
Cuvinte cheie: sticle pe bază de gadoliniu-plumb, spectroscopie IR şi
RES, deşeuri
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26-27 NOI TIPURI DE STICLE CA POTENŢIALI SENZORI PENTRU DETERMINAREA NITRAŢILOR DIN APĂ

NEW TYPES OF GLASS AS POTENTIAL SENSORS TO
DETERMINE THE NITRATES ANIONS
FROM WATER
In this paper is presented a new type of glass that can be used as
potential electrochemical sensor for nitrate anions from aqueous solutions. The
glass sample obtained was analysed by FT-IR and UV-VIS spectroscopy and
cyclic voltammetry (VC). The cyclic voltammetry shows that the current
increase with the increasing of concentration of sodium nitrate from aqueous
solutions. The FT-IR spectrum after VC shows a decreasing of [PbO6] structural
units from the glass, probably increasing in this way the number of free lead
ions (Pb+2) and improving the electrochemical properties of the glass sample.
The decrease in the intensity of the UV-VIS absorption bands after VC shows
that a part of Fe+3 ions convert to Fe+2 ions and pass into solution.
Keywords: glass, sensors, IR spectroscopy, cyclic Anodic, UV-VIS
spectroscopy, nitrates in water
Cuvinte cheie: sticlă, senzori, voltametrie ciclică, spectroscopie IR,
spectroscopie UV-VIS, nitraţi din ape
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26-26 RECICLAREA DEŞEURILOR PROVENITE DE LA BATERIILE AUTO ÎN STICLE PE BAZĂ DE PLUMB

THE RECICLYNG OF THE WASTES PROVIDED
OF AUTO BATTERIES IN LEAD GLASSES
The purpose of this paper was i) to obtained the lead glasses with the
xPb∙(100-x)PbO2 composition where x = 0-15mol % Pb by melt quenching
method and ii) to characterized of the structural and optical properties of the
obtained glasses by investigations of FTIR and UV-VIS spectroscopy in order
to possible applications in the auto battery recycling.
FTIR data show that the accommodation of the host glass with excess
of metallic lead was possible by the conversion of some [PbO6] octahedral
structural units into [PbOn] structural units where n=3 and 4. Then, the increase
of the metallic lead high content in the matrix network will produce to the
deficiency of non-bridging oxygen’s and the formation of UV-VIS bands in
region centred at about 300nm which can be attributed to the electronic
transitions of the lead ions.
Keywords: lead-based bottles, car batteries, spectroscopy UV-VIS and
IR, recycling
Cuvinte cheie: sticle pe bază de plumb, baterii auto, spectroscopie IR
şi UV-VIS, reciclare
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