Session 46 - Nanomaterials in the environment applications and effects

[CEST2019_00928] Photocatalytic Degradation of Tebuconazole Fungicide using Palygorskite-TiO2 nanocomposites.
by Giannakis I., Panagiotaras D., Papoulis D., Gianni E., Stathatos E., Bekiari V., Kalarakis A.N., Panagopoulos G.

In our study a combination of Palygorskite clay mineral with TiO2 nanoparticles used for the decomposition of the common tebuconazole (TEB), C16H22ClN3O, [(RS)-1-p-chlorophenyl-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)-pentan-3-ol], fungicide in water. For this purpose, Palygorskite-TiO2 nanocomposites fabricated using the sol-gel process combined with hydrothermal treatment of the samples under mild conditions. The Palygorskite-TiO2 nanocomposites were characterized by X-Ray diffraction (XRD), scanning electron microscopy (SEM), and N2 specific surface area (SSA) analysis by BET. The total pore volume and SBET was 0.49 cm3/g and 258 m2/g for the Palygorskite 40% - TiO2 60% sample. The Palygorskite 10% - TiO2 90% sample has 0.33 cm3/g and 220 m2/g pore volume and SBET respectively. The highest degradation efficiency 88.4% was achieved for Palygorskite 40% - TiO2 60% sample while commercial TiO2 nanopowder Degussa P25 sample exhibited 33.0% degradation efficiency which is much lower.
The Palygorskite-TiO2 nanocomposites show that they are effective and promising new class of materials for the photocatalytic degradation of TEB fungicide in water.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:27 to 13:30
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00899] TiO2/Graphene Oxide Heterostructures for Photocatalytic Applications
by Giannakopoulou T., Papailias I., Todorova N., Trapalis A., Bahnemann D.

In the present work, TiO2/graphene oxide (GO) heterostructures with different concentrations of GO were synthesized by hydrothermal transformation of Na-titanate in basic solution. The morphology of the prepared materials was observed by X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The transient absorption spectra of the pure TiO2 and composite TiO2/GO materials were collected using laser flash photolysis technique in order to assess photoinduced charge transfer kinetics. Finally, the materials were tested for photocatalytic hydrogen production under solar light irradiation.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:24 to 13:27
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00885] Electrochemical properties of SnO2/rGO nanocomposites
by Todorova N., Giannakopouloy T., Lekakou C., Arabatzis I.,Trapalis C.

SnO2 nanoparticles were deposited on reduced graphene oxide (rGO) to obtain SnO2/rGO composites with high energy storage capacitance. For this purpose, graphite oxide (GtO) was synthesized and hydrothermally treated in presence of Sn precursor. The quantity of GtO was varied to tune the heterostructures’ composition and the particles size of the SnO2.
The XRD and SEM analyses revealed that the GtO was exfoliated, reduced and decorated with SnO2 nano-particles during the hydrothermal treatment. With the increase of GtO quantity the SnO2 particle size decreased from ~30 nm to ~14 nm. The Cyclic Voltammetry analysis showed that the pure rGO exhibited typical supercapacitor behavior. All the SnO2/rGO composites exhibited significantly increased specific capacitance in comparison to the pure SnO2. The SnO2/rGO with the highest GtO content showed capacitance ~ 200 F.g-1 that was comparable to that of the pure rGO. The result was related to the small particles size of SnO2 and their distribution between the rGO sheets.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:18 to 13:21
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00886] Application of Ni loaded FAU zeolites in catalytic conversion of 1,2-dichloroethane towards value-added products
by Góra-Marek K., Śrębowata A., Kowalewski E., Tarach K.A., Pyra K.

The catalytic performance of nickel loaded zeolite materials was found to be dependent on their acidic feature that influenced metal speciation and its dispersion. The selectivity to ethane and ethane of the Ni loaded catalysts increased when reducing both the number of acid sites and average nickel particle size in zeolite catalysts.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:21 to 13:24
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00732] Adsorption of Gatifloxacin from Aqueous Solution with Highly Stable Zr(IV)-Based Porphyrinic Metal-Organic Frameworks
by Chen J.-J., Wang L.-J., Xu G.-J., Wang X., Zhao R.-S.

Water stable Zr-metal–organic framework nanoparticles (PCN-224 NPs) have been solvothermally synthesized. PCN-224 NPs show spherical shape with smooth surface and particle size of approximately 200 nm. PCN-224 NPs can be stable in acid and aqueous solutions, as confirmed by powder X-ray diffraction. Gatifloxacin (GTF) adsorption measurements showed that PCN-224 NPs exhibit a high adsorption capacity of 876 mgg-1. Meanwhile, the adsorption factors, adsorption characteristics, and mechanisms of GTF were investigated in batch adsorption experiments.

Session: 46, Room: D, at Sat, 09/07/2019 - 12:30 to 12:45
Oral presentation in Nanomaterials in the environment applications and effects
[CEST2019_00772] Aqueous synthesized mixed-phase nano-TiO2 photocatalysts for water treatment of both organic and inorganic pollutants
by Chalastara K., Demopoulos G.P.

Nano-sized mixed-phase titanium dioxide (TiO2) particles are synthesized through aqueous hydrolytic precipitation of TiCl4, in an easily-scalable continuously stirred tank reactor, CSTR. Different conditions give tunable mixed phase nanotitania particles consisting of anatase (A), rutile (R) or brookite (B) that are further characterized as photocatalysts in both oxidative and reductive roles and compared with the well-known commercial nanotitania, Evonik P25. Degradation of an organic model compound, methyl orange under UV light irradiation using the newly synthesized TiO2 blends is first investigated. Further, the remediation of selenium inorganic species from simulated waste water is tackled. Selenium (Se) is an element of environmental concern, as it may report to natural waters via industrial effluents as those released from mining and metallurgical operations among other.

Session: 46, Room: D, at Sat, 09/07/2019 - 12:00 to 12:15
Oral presentation in Nanomaterials in the environment applications and effects
[CEST2019_00724] Evaluation of soil loaded with green iron nanoparticles for hexavalent chromium reduction
by Mystrioti C., Mpouras T., Papassiopi N. ,Dermatas D.

Chromate is a pollutant often found in groundwater and considered a serious threat for humans and ecosystem. Iron nanoparticles produced by green tea polyphenols (GT-nZVI) is a powerful reductant, appropriate for the reduction of Cr(VI) to Cr(III). GT-nZVI suspension was initially conceived ideal for direct injection in the contaminated aquifers. However, many studies demonstrated that this suspension presents very low mobility in calcareous aquifers, which are typical in Mediterrannean countries. An alternative mode of GT-nZVI application is the incorporation of nanoiron in a permeable reactive barrier. This option was evaluated experimentally, assuming that the permeable barrier is filled with a calcareous soil previously loaded with nZVI. Namely an amount of soil was loaded with 0.40 mmol of nZVI per gram of soil (S-nZVI) and its efficiency for Cr(VI) removal was evaluated by conducting batch and column tests. Batch tests were carried out by mixing S-nZVI with contaminated groundwater (GW) containing 1300 μg/L Cr(VI), at five doses from 5 to 50 grams of S-nZVI per liter of GW. Chromate concentration dropped below detection limit within 1 day at the highest dose. Reduction kinetics was slower with the other doses but after 20 days Cr(VI) dropped below the limit of 50 ppb at all doses except the lowest. Column tests confirmed the effectiveness of S-nZVI.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:15 to 13:18
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00645] The influence of graphene addition on the properties of composite membranes RG / PAN and their potential application
by Fryczkowska B.

PAN is an inexpensive and popular engineering polymer, which is widely used in membrane techniques: ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO) and pervaporation (PV). It is characterized by good thermal stability, high thermal conductivity, chemical resistance, solubility in many classic solvents, resistance to UV radiation and good mechanical properties. It can be easily modified both chemically and physically.
The paper describes the method of obtaining composite membranes by the phase inversion method of homogeneous dispersion of graphene (RG) in a solution of polyacrylonitrile (PAN) dissolved in N, N-dimethylformamide (DMF). The influence of RG concentration on physicochemical properties, transport and separation properties (removing microplastic), and resistance to fouling of composite was investigated.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:12 to 13:15
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00627] Structuring efficient photocatalysts into bespoke fiber shaped systems for applied water treatment
by Theodorakopoulos G., Romanos G., Katsaros F., Papageorgiou S., Falaras P., Kontos A., Beazi-Katsioti M.

In this study structured photocatalytic systems were successfully developed by a facile method. Polymeric (Alginate) molds, settled the basis in order to effectively disperse and stabilize nanoparticles of an efficient, copper augmented photocatalyst (Degussa P25), which after removal of the polymer by a pyrolytic or calcination-sintering procedure, were shaped in the form of all-ceramic hollow fibers (HFs) with enhanced photocatalytic and mechanical properties and excellent resistance to attrition. The structural and morphological properties have been studied using LN2 porosimetry, XRD, SEM and Raman spectroscopy. The experimental campaign for elucidating the photocatalytic performance encompassed batch experiments, where the abatement of a prototype organic pollutant (Methyl Orange) was investigated in the dark and under UV irradiation. The obtained performance was benchmarked against that of a prototype photocatalyst implemented in slurry or thin film reactors. The role and the contribution of zero-valent Cu nanoparticles in the photocatalytic mechanism, as well as of carbon residues from the pyrolytic procedure, were also examined.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:09 to 13:12
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00563] Cobalt- and copper-modified fly ash nanozeolites for environmental protection systems
by Boycheva S., Marinov I., Lazarova H., Zgureva D., Václavíková M., Popova M.

In the present study, copper- (Cu-FAZ) and cobalt-modified (Co-FAZ) fly ash zeolites (FAZ) were prepared by an incipient wetness impregnation technique, and the loading of 6 wt. % copper or cobalt in the zeolite Na-X framework was achieved. Cu-FAZ and Co-FAZ were investigated by X-ray diffraction to clarify the state of Cu and Co into the FAZ matrix, while surface studies by nitrogen adsorption/desorption technique were carried out to study the effect of modification on the FAZ surface characteristics. Modified FAZ were investigated as heterogeneous Fenton-type catalysts for oxidative degradation of organic pollutants from waters.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:06 to 13:09
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00565] Removal of Cr(VI) under flow conditions using a green nano-iron loaded resin
by Toli A., Mystrioti C., Xenidis A., Papassiopi N.

A new nanocomposite material, consisting of nanoiron incorporated in cationic resin beads, was evaluated for the removal of Cr(VI) under flow conditions, by conducting column experiments. An aqueous solution containing Cr(VI) 5 mg/L and NaCl 0.01 M as inert electrolyte was introduced in the column applying a continuous up-flow mode. The tests were carried out using a column with diameter 2.6 cm and the flowrate was stepwise increased, reducing the Empty Bed Contact Time (EBCT) from 38 to 2.3 minutes. The reduction of Cr(VI) was found to depend on the residence time of the solution inside the bed of R-nFe, and the pH of flowing solution. The column has treated an amount of solution equivalent to 640 bed volumes without appearance of the Cr(VI) breakthrough. Also, when the feeding solution was spiked with both Cr(VI) and Ni, the effluents were free from the two elements, indicating that the nanocomposite material can be equally efficient in the case of mixed contamination.

Session: 46, Room: D, at Sat, 09/07/2019 - 11:45 to 12:00
Oral presentation in Nanomaterials in the environment applications and effects
[CEST2019_00501] Interactions between Plants and Rare Earth Oxide Nanoparticles
by Zhang Z.Y.

Rare earth oxide nanoparticles (REO NPs) can be released into the environment from various application routes, but their effects on the ecosystem are still little known. In this study, we exposed cucumber seedlings to suspensions of La2O3 and CeO2 NPs for 14 d. Phytotoxicity of the two REO NPs was assessed and their distribution and transformation in plant tissues were investigated. CeO2 NPs had no toxicity to cucumber at all tested concentrations, while La2O3 NPs showed significant inhibition on root elongation, biomass, as well as induced more ROS and cell death in roots. The different distribution and speciation of Ce and in plants were determined by synchrotron-based micro X-ray fluorescence microscopy (SR-XRF) and X-ray absorption spectroscopy (XAS). In the aerial parts, all of La was combined with phosphate or carboxylic group while only a fraction of Ce was changed to Ce(III)-carboxyl complexes, implying that La2O3 acted as its ionic form while CeO2 displayed the behavior of particles or particle-ion mixtures. The higher dissolution of La2O3 than CeO2 NPs might be the reason for their significant difference in phytotoxicity and transporting behaviors in cucumber plants.

Session: 46, Room: D, at Sat, 09/07/2019 - 12:15 to 12:30
Oral presentation in Nanomaterials in the environment applications and effects
[CEST2019_00505] Evaluation of risk and the beneficial effects of synthesized nano silver-based disinfectant on poultry mortality and health
by Kumar I., Bhattacharya J.

This study was evaluated for the potential use of nanosilver (nAg) as a disinfectant and antimicrobial growth promoter supplement for the poultry. The experiments were conducted in the Kangsabati river basin region, in West Medinipur district, West Bengal, India for six months. Two poultry farms were adopted for the experiment. The rural economy of this region from Jhargram to Barkola is heavily dependent on contract poultry farming. The water samples were collected from the water source of poultry farm which has been used for poultry drinking purpose. The bacteriological analysis of water sample revealed that the total bacterial count (total coliform and E. coli) were higher than the acceptable standards. The bacterial loads badly affected the growth performance and health of the poultry. For disinfection, a number of chemical compounds (like formaldehyde, calcium hypochloride, sodium hypochloride, and sodium bicarbonate) have been used in typical commercial formulations. However, the effects of all these chemical compounds have not been significant over time. As a part of our research-to-market initiative, we used nanosilver (nAg) formulation as a disinfectant. The nAg formulation was synthesized by hydrothermal technique and characterized by UV-visible, TEM, SEM, and EDX. The obtained results revealed that the mortality rate of poultry was reduced due to nAg formulation compared to the mortality rate of the negative control.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:03 to 13:06
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00458] Adsorption of heavy metals (hexavalent chromium, lead, manganese and cadmium) on multiwall carbon nanotubes
by Mpouras T., Papadaki S., Dermatas D.,Papassiopi N.

Nanotechnology holds great potential in the sector of water/wastewater treatment since it is considered as an advanced technology for improving water quality. Carbon nanotubes is a carbonaceous material that shows exceptional adsorption capacity for the removal of heavy metals due to their novel properties. Thus their application for the treatment of industrial wastewater or contaminated groundwater exhibits high interest. In this study the efficiency of multiwall carbon nanotubes as adsorbent for hexavalent chromium, manganese, lead and cadmium removal as a function of pH and the initial concentration of heavy metal is investigated. In addition, the occurrence of any competitive effects amongst the aforementioned metals during adsorption is investigated. For this reason batch experiments are performed keeping constant the concentration of multiwall carbon nanotubes (2 g/L) and the contact time (5 h).

Session: 46, Room: D, at Sat, 09/07/2019 - 11:30 to 11:45
Oral presentation in Nanomaterials in the environment applications and effects
[CEST2019_00261] Enhanced of TiO2-Ag photocatalysis performance for removal of methylene blue in the presence of acetone
by Harja M., Duduman Nutescu C., Apostolescu G.A., Gómez De Salazar J.M., Gómez De Castro C., Sescu A.M., Favier L., Ciobanu G.

In the present study, the photocatalytic degradation of methylene blue (MB), using TiO2-Ag synthesized by sol-gel method, as a catalyst under UV light, was studied. Tests were carried out in a batch reactor, magnetically stirred, with external irradiation using an UV-B. The effects of some parameters, such as catalyst dosage and initial acetone concentration were investigated. Results showed that the optimal catalyst concentration was 0.03 g/L, at a concentration of MB of 1.25∙10-5 mol/L. The results are very promising using TiO2-Ag as photocatalyst, especially in the presence of acetone as photosensitizer; the degradation degree increases from 60% for raw TiO2, to 92.38% for TiO2-Ag and 0.1% acetone and respectively, 97.25% for 0.2% acetone. The photocatalysis followed a pseudo-first order reaction kinetics, with rate constants ranging from 0.0009 to 0.11 min-1 under the studied conditions.

Session: 46, Room: D, at Sat, 09/07/2019 - 13:00 to 13:03
Flash presentation in Nanomaterials in the environment applications and effects
[CEST2019_00148] One-step Synthesis of TiO2/ZnO Nanocomposites by Refluxing Methods for Photochemical Degradation of Humic Acid
by Fadillah G., Hidayat R., Wahyuningsih S.

Synthesis of TiO2/ZnO nanocomposites (TZN) through the one-step refluxing method for photochemical degradation of humic acid (HA) in aqueous solution has been studied. Titanium isopropoxide (TTIP) and ZnSO4.7H2O were used as a starting material under base solution at 120 oC for 24 hours. TZN materials were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), the thermogravimetric analysis and differential thermal analysis (TG-DTA). The characterization showed that there is a specific diffraction peak from TiO2 (2θ = 25.30) and ZnO (2θ = 36.33) as a composite with the crystal size 41.55 and 15.76 nm, respectively. The material morphology showed the granular shape of the composite and have good thermal stability. The photochemical activity was evaluated by photocatalytic degradation of HA under UV254¬ light. The optimum condition was found at pH 4.0, and times at 30 minutes. This study confirmed that the TZN material can decrease the HA concentration. Furthermore, the maximum result of the experiment was a 95-98% degradation of HA in aqueous solution.

Session: 46, Room: D, at Sat, 09/07/2019 - 12:45 to 13:00
Oral presentation in Nanomaterials in the environment applications and effects