2017, Volume 63(67), Issue 3 (September)
Contents
pages 1- 8 Download
Photocatalytic and Photo-Fenton Degradation of Ibuprophen under Solar Light Irradiation
MIHAELA DARIE, "Gheorghe Asachi" Technical University of
Iaşi, Faculty of Chemical Engineering and Environmental Protection,
ddariemihaela@yahoo.com
GABRIELA CARJA,
"Gheorghe Asachi" Technical University of
Iaşi, Faculty of Chemical Engineering and Environmental Protection,
gcarja@ch.tuiasi.ro
pages 9 - 21 Download
Abstract
In this work, the degradation of pharmaceutical agent ibuprofen by
photocatalysis and photo-Fenton catalysis, using artificial visible
light irradiation and H2O2 as Fenton reagent, was carried out. Two
efficient Fe/LDHs photocatalysts with different iron content were
fabricated. First, the LDH precursor with Zn2+ and Al3+ as di- and
trivalent brucite-like cations (Zn2+/Al3+ = 3/1) was obtained by
co-precipitation method and denoted as Zn3Al. Then, by the
structural reconstruction of the calcined Zn3Al in aqueous solution
of FeSO4∙7H2O, two Fe/LDH- based nanocomposites were obtained and
denoted as Fe(1%)Zn3Al and Fe(4%)Zn3Al. The structural and optical
properties of the samples were studied by XRD, FTIR and UV-Vis
techniques. The photocatalytic tests were performed using a solar
simulator as irradiation source. Photocatalytic results showed that
the novel catalysts is efficient for the ibuprofen degradation. A
remarkable enhancement of Ibuprofen degradation was obtained in the
case of photo-Fenton process, up to 89% by Fe(1%)Zn3Al
nanocomposite. Increasing the content of Fe in the catalysts showed
an insignificant effect in enhancing the catalyst efficiency for
ibuprofen removal.
Keywords: photocatalyst; ibuprofen; photo-Fenton; solar photodegradation.
Opportunity to Apply Thermal Decomposition of Spruce Bark after Extractives Recovery
OANA ALEXANDRA PĂTRĂUŢANU, "Gheorghe Asachi" Technical
University of Iaşi, Faculty of Chemical Engineering and
Environmental Protection
MIHAI BREBU, "Petru Poni" Institute of Macromolecular
Chemistry, Iaşi
VALENTIN I. POPA, "Gheorghe Asachi" Technical University of
Iaşi, Faculty of Chemical Engineering and Environmental Protection
IRINA VOLF, "Gheorghe Asachi" Technical University of Iaşi,
Faculty of Chemical Engineering and Environmental Protection,
iwolf@tuiasi.ro
pages 23 - 33 Download
Abstract
The work explores the possibility to use the thermal decomposition
of spruce bark (Picea Abies) in a second biorefinery flow
sheet. Spruce bark was characterised and humidity, ash,
hemicelluloses, cellulose and lignin content were determined. For
the recovery of extractives two procedures were applied: the biomass
was extracted with toluene-ethanol mixture using a conventional
extraction and a 70% ethanol solution was used in an ultrasound
assisted extraction process. In both cases the solid waste was
subjected to pyrolysis conducted at 550°C under relatively low
heating rate of 10°C/min. The aqueous phase was analysed by GC-MS.
Similarities and some differences are highlighted by the
GC-chromatograms and NP-gram characterisation, depending on the
extraction procedures applied.
Keywords: biomass; extractives; pyrolysis;
GC-MS; NP-gram.
Cellulosic Fibers from Miscanthus
CRISTIAN IONUȚ SANDU, "Gheorghe Asachi" Technical University of Iaşi,
Faculty of Chemical Engineering and Environmental Protection
ANA-MARIA
CHEȘCĂ, "Gheorghe Asachi" Technical University of Iaşi, Faculty of Chemical
Engineering and Environmental Protection
ADRIAN CĂTĂLIN PUIȚEL,
"Gheorghe
Asachi" Technical University of Iaşi, Faculty of Chemical Engineering and
Environmental Protection
DAN GAVRILESCU, "Gheorghe Asachi" Technical
University of Iaşi, Faculty of Chemical Engineering and Environmental
Protection, gda@tuiasi.ro
pages 35 - 46 Download
Abstract
Miscanthus is an important biomass crop and has an
important role in the sustainable production of renewable fuels and
chemicals. It is currently used as a source of heat and electricity, or
converted into biofuel products. There are many possibilities to valorize
Miscanthus crops: combustion, gasification and pyrolysis for
energy; liquefaction and hydrolysis for chemicals; delignification for
cellulosic fibers. Chemical composition of Miscanthus is
encouraging regarding its cellulose and lignin content, making them suitable
for delignification. Miscanthus pulp can be obtained by usual
delignification processes, among them soda cooking being very attractive.
Pulps having different yields and lignin content were obtained by suitable
choosing of the cooking parameters: NaOH addition, time and temperature. The
strength properties of pulp mainly depended on its lignin content.
Lignin-rich pulps show high compressive strength, being appropriate in paper
manufacturing for corrugated board production.
Keywords: Miscanthus
crop; soda cooking; chemical pulp; pulp properties; paper.
Biosorption Potential of the Main Fractions Separated from Peat (Poiana Stampei, Romania)
SILVIA PRUTEANU, "Gheorghe Asachi" Technical University of Iaşi, Faculty
of Chemical Engineering and Environmental Protection
LAURA BULGARIU,
"Gheorghe Asachi" Technical University of Iaşi, Faculty of Chemical
Engineering and Environmental Protection,
lbulg@ch.tuiasi.ro
MARIA GAVRILESCU,
"Gheorghe Asachi" Technical University of Iaşi, Faculty of Chemical
Engineering and Environmental Protection
pages 47 - 56 Download
Abstract
In this study it was investigated the separation possibility
of the main organic fraction of peat (Poiana Stampei, Romania), consisting
in humic substances and cellulosic waste, for its use as biosorbents in the
removal process of Cu(II) ions from aqueous solution. In order to separate
the two fractions, the peat was treated with sodium hydroxide solutions of
different concentrations (0.1 – 4.0 N), at two different temperatures (20
and 50°C) for 3 h of mixing. In this way, only the solubilisation of humic
substances from the peat composition takes place, which can be separated
from cellulosic waste by filtration. After filtration, the humic substances
were re-precipitated in strong acid media (pH < 1.0), and then both obtained
fractions were washed and dried in air. The efficiency of separation process
was evaluated in each case. All resulted fractions were used as biosorbents
for the removal of Cu(II) ions from aqueous solution. The experimental
results have shown that the fractions separated by the treatment of peat
with 2N NaOH solution at 50°C exhibit the highest biosorption capacities.
Keywords: peat; humic substances; cellulosic waste; Cu(II) ions;
biosorption.
Pb(II) Removal from Aqueous Solutions by Using Wastes of Pinus Strobus Bark
LAVINIA TOFAN, "Gheorghe Asachi" Technical University of Iaşi, Faculty
of Chemical Engineering and Environmental Protection
CARMEN PĂDURARU,
"Gheorghe Asachi" Technical University of Iaşi, Faculty of Chemical
Engineering and Environmental Protection,
cpadur2005@yahoo.com
ION BUNIA,
"Gheorghe Asachi"
Technical University of Iaşi, Faculty of Chemical Engineering and
Environmental Protection
ROXANA LAURA MIHĂILESCU AMĂLINEI,
"Gheorghe
Asachi" Technical University of Iaşi, Faculty of Chemical Engineering and
Environmental Protection
ANCA MIRON, "Gheorghe Asachi" Technical
University of Iaşi, Faculty of Chemical Engineering and Environmental
Protection
pages 57 - 70 Download
Abstract
The influence of significant operational parameters on the
Pb(II) sorption process by Romanian Pinus strobus has been studied
in batch conditions. The uptake of Pb(II) from solutions with different
initial concentrations of Pb(II) increased progressively with increasing
initial pH from 2 to 5-5.5. The percent removal of Pb(II) varied from 84% to
98% for an increase of bark waste dose to 4 at 60 g/ L. The sorption
isotherm studies clearly indicated that the sorptive behavior of Pb(II) ions
on Romanian Pinus strobus bark under study satisfies not only the
Langmuir assumptions, but also the Freundlich assumption. The calculated
values for the isothermal thermodynamic parameters show that Pb(II) ions
retention by pine bark is a spontaneous process of endothermic and chemical
nature. The sorption kinetics for Pb(II) ions removal from aqueous solutions
was very well described by pseudo-second order model.
Keywords: Pinus
strobus; bark; sorption; waste; lead.