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Photo-Fenton processes activated by biodegradable Fe(III)–EDDS complexes have attracted huge attention from the scientific community, but the operative mechanism of the photo-activation of H2O2 in the presence of Fe(III)–EDDS has not been fully clarified yet. The application of the Fe(III)–EDDS complex in Fenton and photo-Fenton (mainly under UV-B light) processes, using 4-chlorophenol (4-CP) as a model pollutant was explored to give insights into the operative mechanism. Furthermore, the potential synergistic contribution of soybean peroxidase (SBP) was investigated, since it has been reported that upon irradiation of Fe(III)–EDDS the production of H2O2 can occur. SBP did not boost the 4-CP degradation, suggesting that the possibly produced H2O2 reacts immediately with the Fe(II) ion with a quick kinetics that does not allow the diffusion of H2O2 into the bulk of the solution (i.e., outside the solvent cage of the complex). So, a concerted mechanism in which the photochemically produced H2O2 and Fe(II) react inside the hydration sphere of the Fe(III)–EDDS complex is proposed. Graphical abstract

We demonstrated that controlled periodic illumination (CPI) is unable to increase the quantum yield (or photoefficiency) of the photocatalytic process. Nevertheless, choosing the appropriate experi...

Water pollution is the most serious problem threatening global water resources. The release of both natural and anthropogenic factors in the aquatic environment is affecting the quality of water bodies, with Contaminants of Emerging Concern (CECs) being one of the major issues. In recent years, the availability of robust and sensitive analytical methods has allowed the detection and identification of a wide variety of pollutants. Pharmaceutically Active Compounds (PhACs) represent one large category of CECs detected in the aquatic environment, posing serious threats to human health and ecosystems. Hence, there is an urgent need for a better understanding of their environmental occurrence, fate, exposure-associated risks, and degradation in order to regulate exposure to pharmaceuticals in the environment. This review covers the current trends, newly developed state-of-the-art analytical methods, their challenges for PhACs detection in different water matrices, and the occurrence patterns in the aquatic environment. We also make a compressive assessment of the ineffective classic drinking water treatment plants (DWTPs) and the novel technologies such as membrane filtration and advanced oxidation processes that have been implemented to upgrade DWTPs. Their efficiency in removing PhACs is here discussed, as well as other embryonic technologies as promising solutions. The aim of this review article is to provide a comprehensive summary of the pathways and fate of PhACs in the environment, solutions for improving their monitoring assessments and the best methods for their removal in drinking water treatment plants.

Advanced oxidation processes (AOPs) have been studied since many years for the removal of organic bio recalcitrant molecules and proposed as tertiary treatment for effluent waters. Mostly ozonation and UV-H2O2 have found application in water treatment utilities plant. It is highly relevant establish reliable measurement for real-time monitoring of the AOPs course in order to allowing fast intervention in case of malfunctioning. Sophisticated and powerful analytical techniques based on mass spectrometry do not fulfil requirements for being used inline. Surrogate-based models have been therefore considered for their suitability, together with the use of carefully selected indicator molecules for the creation of correlation models representative of groups of pollutants. The most relevant features of the above mentioned approaches are discussed evidencing their strength and weakness as well as their complementary role when optimizing AOP, at laboratory scale for an in depth system characterization, and at plant scale for the process monitoring during its application at real cases.

International audience; Magnetic particles (MPs) coated with humic acid (HA) prepared under anoxic atmosphere were tested as heterogeneous photo-Fenton catalyst for the activation of hydrogen peroxide (H 2 O 2) and persulfate (S 2 O 8 2−) using Bisphenol A (BPA) as a model pollutant. The role of HA coating, pH value and H 2 O 2 /S 2 O 8 2− concentration were investigated. A positive contribution of HA coating on H 2 O 2 and S 2 O 8 2− activation was found. The highest BPA degradation rates were achieved at acidic conditions (pH 3) with both H 2 O 2 and S 2 O 8 2− , however persulfate showed a significant efficiency even at pH 6, interesting feature in the light of decreasing the wastewater treatment costs. By the addition of selective quenching agents, % OH and SO 4 %-were identified as the main reactive species involved in the BPA abatement. An important contribution of the S 2 O 8 2− photolysis on the overall BPA transformation was highlighted. The reuse of the catalyst was investigated and similar efficiency using H 2 O 2 and S 2 O 8 2− activation was observed until the third catalytic cycle. Experiments carried out using real wastewater samples, showed a good, even if less efficient compared to pure water, BPA removal.

Soluble bioorganic substances (SBOs) are soluble macromolecular substances isolated from residual biomasses, featuring physical–chemical properties analogous to natural organic matter present in soils, in particular humic acids. SBO’s structure possesses different functionalities, able to chelate metal ions, as well as absorb light in the ultraviolet–visible (UV–vis) spectral interval, showing a certain photoactivity. These properties have been exploited for environmental purposes, in particular the photodegradation of aqueous pollutants. Herein, several examples of the photoactivity of different SBOs are reported, with a focus on the nature of the reactive species generated by SBO upon UV–vis irradiation. Due to their capability to form complexes with Fe(III), SBOs have been demonstrated to be interesting auxiliaries in photo-Fenton-like processes for the degradation of pollutants in aqueous solutions at near-neutral pH. A further development of SBO is their use in heterogeneous photocatalysis to favor the recovery and reuse of the photoactive agent. For this purpose, different materials have been synthesized, having an oxide core and a SBO shell. A detailed characterization of these materials is reported together with their performances in the photodegradation of organic pollutants.

A literature selection of the properties and performances of perovskite-type LaFeO3 prepared by solution combustion synthesis from different fuels is proposed in relation with their photocatalytic activity, particularly for the abatement of wastewater organic pollutants. In solution combustion synthesis, the fuel has the triple role of reducer, complexing agent and microstructural template, influencing both chemical–physical and photocatalytic properties of the perovskite powder. A specific dissertation is dedicated to LaFeO3 prepared by citric acid or by soluble bio-based substances extracted from urban waste, which are examined for the degradation of some phenolic derivatives and cationic dyes. Critical aspects related to the synthetic protocol are evidenced and LaFeO3 stability is also studied, considering the role of released substances, which can simultaneously initiate a photocatalytic process. It is highlighted that the fuel affects the reproducibility of LaFeO3 performance in the abatement of organic pollutants.

VUV-irradiation experiments with aqueous solutions of melamine and related triazine derivatives were carried out in the presence or absence of molecular oxygen. Substrate degradation, total organic carbon and evolution profiles of intermediates were monitored. Relevant mineralization of the substrates was observed, in particular for melamine, its extent depending on the concentration of dissolved O2 and on the number of amino substituents at the s-triazine moiety of the substrate. In all experiments, cyanuric acid was found to be the only persistent final product. Experimental results indicate that the route of reactions leading to mineralization is independent of that leading to amino group substitution. Mechanistic hypotheses are proposed and compared with findings coming from TiO2-based photocatalysis.

In this study, we demonstrated that BaCO3 and NH3SO3 can be conveniently used as BaSO4 precursors. BaSO4 is obtained by treating the precursor, BaCO3, with a sulfate-containing solution, owing to the lower solubility product constant of BaSO4 compared to that of BaCO3. Using this procedure, BaSO4 particles with pseudo-cubic/prismatic morphology are obtained. In this case, temperature and reaction time have little influence on morphology, which is mainly controlled by supersaturation and sulfate concentration. Sulfate counter ion also affects the morphology, but its effect is less pronounced. The hydrolysis of NH3SO3 in the presence of soluble barium salts produces BaSO4 particles, and different kinds of morphology can be obtained, encompassing rounded and nearly spherical particles, prismatic and pseudo-cubic, irregular shapes with flat and well-developed facets, and even hopper crystals. In these syntheses, temperature and pH are playing a major role in controlling sulfamic acid hydrolysis and, therefore, supersaturation, with remarkable consequences for crystal nucleation and growth. Considering that BaSO4 finds applications in many sectors and for different purposes, the variety of particle size and shape reported in this study can potentially improve the performance of the materials in which BaSO4 particles are employed.

Anatase nanoparticles in suspension have demonstrated high photoactivity that can be exploited for pollutant removal in water phases. The main drawback of this system is the difficulty of recovering (and eventually reusing) the nanoparticles after their use, and the possible interference of inorganic salts (e.g., sulfates) that can reduce the performance of the photocatalyst. The present work describes the development of a cordierite-honeycomb-supported TiO2 film to eliminate the problems of catalyst recovery. The catalyst was then tested against phenol in the presence of increasing concentrations of sulfates in a specially developed recirculating modular photoreactor, able to accommodate the supported catalyst and scalable for application at industrial level. The effect of SO42− was evaluated at different concentrations, showing a slight deactivation only at very high sulfate concentration (≥3 g L−1). Lastly, in the framework of the EU project Project Ô, the catalyst was tested in the treatment of real wastewater from a textile company containing a relevant concentration of sulfates, highlighting the stability of the photocatalyst.

In the present work, the photo-Fenton degradation of pentachlorophenol (PCP, 1 mg/L) has been studied under simulated and natural solar irradiation, moreover, the effect on the process efficiency of urban waste-derived soluble bio-based substances (SBO), structurally comparable to humic acids, has been investigated. Experiments showed a crucial role of PCP photolysis, present in the solar pilot plant and hindered by the Pyrex&reg, filter present in the solar simulator. Indeed, the SBO screen negatively affects PCP degradation when working under natural solar light, where the photolysis of PCP is relevant. In contrast, in the absence of PCP photolysis, a significant improvement of the photo-Fenton process was observed when added to SBO. Furthermore, SBO were able to extend the application of the photo-Fenton process at circumneutral pH values, due to their ability to complex iron, avoiding its precipitation as oxides or hydroxides. This positive effect has been observed at higher concentration of Fe(II) (4 mg/L), whereas at 1 mg/L, the degradation rates of PCP were comparable in the presence and absence of SBO.

Urban wastes are a potential source of environment contamination, especially when they are not properly disposed. Nowadays, researchers are finding innovative solutions for recycling and reusing wastes in order to favour a sustainable development from the viewpoint of circular economy. In this context, the lignin-like fraction of biomass derived from Green Compost is a cost-effective source of soluble Bio-Based Substances (BBS-GC), namely complex macromolecules/supramolecular aggregates characterized by adsorbing and photosensitizing properties. In this work BBS-GC were immobilized on a silica support (SBA-15) and the chemico-physical properties of the resulting hybrid material (BBS-SBA) were analysed by zeta-potential measurements, nitrogen adsorption at 77K and micro-calorimetric techniques. Successively, the BBS-SBA photosensitizing and adsorption abilities were tested. Adsorption in the dark of Rhodamine B and Orange II on BBS-SBA and their degradation upon irradiation under simulated solar light were shown, together with the formation of hydroxyl radicals detected by Electron Paramagnetic Resonance spectroscopy. Furthermore, the adsorption of six inorganic ions (Al, Ni, Mn, As, Hg, Cr) on BBS-SBA was studied in pure water at two different pH values and in a landfill leachate, showing the good potential of this kind of materials in the removal of wastewater contaminants.

The valorization of low-cost biobased resources (such as biomasses and their derivatives) as alternative feedstock for the preparation of innovative sustainable materials allows both economic and environmental benefits, for instance when these materials enhance the photodegradation of organic pollutants in water remediation processes. This chapter presents the physicochemical features of biobased substances (BBS) isolated from urban organic residues, and it reports on their performances as chemical auxiliaries in advanced oxidation processes (AOPs). In the homogeneous phase, BBS can indeed promote the direct oxidation of organic pollutants through the formation of many reactive species, and it can also allow running Fenton and photo-Fenton processes at circumneutral pH. Additionally, BBS can be used in heterogeneous phase. In addition, the preparation, characterization, and pollutant photodegradation efficiency of novel heterogeneous systems based on hybrid magnet-responsive materials functionalized with biobased substances is discussed, whereas the functionalization with oxidative enzymes is presented as well.

[EN] The photodegradation of an aqueous solution of diclofenac (DCF) has been attempted in the presence of hydrogen peroxide and organic/inorganic hybrid magnetic materials under simulated and real solar light. The hybrid magnetic materials have been prepared via coprecipitation synthesis starting from iron(II) and iron(III) inorganic salts in the presence of bioderived organic products (i.e., chitosan or bio-based substances isolated from commercially available composted urban biowastes) acting as stabilizers of the iron-containing phase. In addition to the as prepared hybrid materials, the corresponding materials obtained after a pyrolytic step at low temperature (550 degrees C) have been tested. The obtained results evidenced the capability of the materials to activate hydrogen peroxide at mild pH promoting DCF (photo) degradation. All the materials feature also as adsorbents since a decrease of DCF is observed also when working in the dark and in the absence of hydrogen peroxide., This work was realized with financial support for academic interchange from the Marie Sklodowska-Curie Research and Innovation Staff Exchange project, funded by the European Commission H2020-MSCA-RISE-2014 within the framework of the research project Mat4treaT (Project number: 645,551). Politecnico di Torino is gratefully acknowledged for funding project Starting Grant RTD (project number: 54_RSG17NIR01).

Anatase nanoparticles in suspension have demonstrated high photoactivity that can be exploited for pollutant removal in water phases. The main drawback of this system is the difficulty of recovering (and eventually reusing) the nanoparticles after their use, and the possible interference of inorganic salts (e.g., sulfates) that can reduce the performance of the photocatalyst. The present work describes the development of a cordierite-honeycomb-supported TiO2 film to eliminate the problems of catalyst recovery. The catalyst was then tested against phenol in the presence of increasing concentrations of sulfates in a specially developed recirculating modular photoreactor, able to accommodate the supported catalyst and scalable for application at industrial level. The effect of SO42&minus, was evaluated at different concentrations, showing a slight deactivation only at very high sulfate concentration (&ge, 3 g L&minus, 1). Lastly, in the framework of the EU project Project &Ocirc, the catalyst was tested in the treatment of real wastewater from a textile company containing a relevant concentration of sulfates, highlighting the stability of the photocatalyst.

Hybrid magnetite/maghemite nanoparticles (MNP) coated with waste-sourced bio-based substances (BBS) were synthesized and studied for the degradation of phenol, chosen as a model pollutant, in water. A systematic study was undertaken in order to rationalize MNP&ndash, BBS behavior and optimize their performance. The effect of experimental parameters, such as light irradiation, addition of hydrogen peroxide, and the ratio between hydrogen peroxide and MNP&ndash, BBS concentrations, was studied. The generation of hydroxyl radicals was assessed, and the recovery and re-cycle of the material was investigated. Our results indicate that phenol degradation could be attained by both Fenton and photo-Fenton processes, with higher efficiency in dark condition and in the presence of a suitable amount of hydrogen peroxide. Evidence was obtained for the roles of iron ions leached from the materials as well as of organic matter released in the solution upon partial photodegradation of the organic coating. The reusability tests indicated a lower but still valid performance of the material. Optimization of the experimental conditions was performed to achieve the highest efficiency in substrate degradation, and fundamental insights into the mechanism of the MNP&ndash, BBS Fenton-like reaction were obtained.

This study investigated the role of two technical features of borehole heat exchangers (BHEs) in causing impacts on groundwater quality: the use of propylene glycol (PG) and other additives in heat-carrier fluids and the BHE grouting. The PG is the most diffused antifreeze compound used in heat-carrier fluids circulating into the ground loops. Laboratory-scale experiments were performed to simulate the release of PG into soil–water microcosms. PG itself is not toxic, but it is a potential organic nutrient able to stimulate the micro-organisms’ metabolism, thus resulting in O2 consumption and subsequent decrease in redox potential of the system. Indeed, a leaching of the main heavy metals was observed: Fe, Mn and Ni ions reached 102–104 μg l−1 concentrations after 60 days. Secondly, the role of BHE grouting in changing the hydraulic conditions of aquifers was investigated because defects and voids in the grout may increase the hydraulic conductivity along the boreholes, leading to inter-aquifer flux. A field-scale experiment was performed by grouting a 7-m-long pilot BHE, and many defects and void spaces were detected along the BHE. A simplified analytical model was thus applied to detect the magnitude of the inter-aquifer flux. Basing the calculations on typical hydraulic parameters of the alluvial aquifer of Piedmont Po Plain (NW Italy), the downward flux is up to 2.65 cubic metres per day in the worst scenarios with high head difference and thin separation layer between two superposed aquifers.

[EN] The valorization of olive oil mill solid wastes (OMW) has been addressed by considering it as a possible source of humic-like substances (HLSs), to be used as auxiliary substances for photo-Fenton, employing caffeine as a target pollutant to test the efficiency of this approach. The OMW-HLS isolation encompassed the OMW basic hydrolysis, followed by ultrafiltration and drying. OMW-HLS structural features have been investigated by means of laser light scattering, fluorescence, size exclusion chromatography, and thermogravimetric analysis; moreover, the capability of OMW-HLS to generate reactive species under irradiation has been investigated using spin-trap electronic paramagnetic resonance. The caffeine degradation by means of photo-Fenton process driven at pH = 5 was significantly increased by the addition of 10 mg/L of OMW-HLS. Under the mechanistic point of view, it could be hypothesized that singlet oxygen is not playing a relevant role, whereas other oxidants (mainly OH center dot radicals) can be considered as the key species in promoting caffeine degradation., Authors want to acknowledge the financial support of Spanish Ministerio de Economia y Competitividad (CTQ2015-69832-C04) and European Union (645551-RISE-2014, MAT4-TREAT).

In this study, chitosan and bio-based substances (BBS) obtained from composted biowaste were used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs) via coprecipitation method. A pyrolysis treatment was carried out on both biopolymers at 550 °C, and their consequent conversion into a carbon matrix was followed by means of different physicochemical characterization techniques (mainly FTIR spectroscopy and XRD), whereas magnetic properties were evaluated by magnetization curves. The prepared materials were tested in water remediation processes from arsenic (As) species (both inorganic and organic forms). These tests, explained by means of the most common adsorption models, evidenced that the best performances were reached by both materials obtained after pyrolysis treatments, pointing out the promising application of such magnet-sensitive materials as easy-recoverable tools for water purification treatments. Fil: Nisticò, Roberto. Università di Torino; Italia. Politecnico di Torino; Italia Fil: Celi, Luisella R.. Università di Torino; Italia Fil: Bianco Prevot, Alessandra. Università di Torino; Italia Fil: Carlos, Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina Fil: Magnacca, Giuliana. Nanostructured Interfaces And Surfaces; Italia. Università di Torino; Italia Fil: Zanzo, Elena. Università di Torino; Italia Fil: Martin, Maria. Università di Torino; Italia

A waste-derived photoactive substance sourced from the green fraction of urban refuses (CVT230) was immobilized on different types of silica support, one amorphous and the other two with controlled porosity (HMS and SBA). In this fashion, three hybrid systems were obtained, which contained CVT230 as an insoluble photoactive component. They were tested in the photodegradation of 4-methylphenol in aqueous solution irradiated by simulated solar light and results showed that they are able to promote the total photodegradation of the pollutant. The materials, both before and after irradiation, were characterized by high-resolution transmission electron microscopy (TEM), small angle X-ray scattering (SAXS), N2 gas-volumetric adsorption, infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The SBA silica hybrid system showed the best performance in terms of stability and reusability, after multiple irradiation cycles. This behaviour can be correlated to the silica morphology and texture, being capable to better allocate and stabilize the CVT230 molecules.

Improving understanding on groundwater chemistry is a key priority for water supply from groundwater resources, especially in developing countries. A hydrochemical study was performed in an area of SW Guatemala (Samala River basin), where water supply to population is groundwater-based and no systematic studies on its groundwater resources have been performed so far. Traditional hydrochemical analyses on major ions and some trace elements metals coupled with chemometric approach were performed, including principal component analysis and hierarchical clustering analysis. Results evidence that chemical differentiation is linked to the spatial distribution of sampled waters. The most common hydrochemical facies, bicarbonate calcium and magnesium, is linked to infiltration of meteoric waters in recharge areas represented by highlands surrounding Xela caldera, a wide plateau where most of population is concentrated. This trend undergoes chemical evolution in proximity of active volcanic complexes in the southern area, with enrichment in sulphate, chloride and magnesium. Chemical evolution also occurs towards the centre of Xela caldera due to slow circulation in aquifer and consequent sodium enrichment due to ion exchange with the porous medium. Water quality did not reveal severe concerns, even though some sources of contamination could be identified; in particular, agriculture and urban wastewater could be responsible for observed threshold exceedances in nitrate and lead. This integrated multi-approach to hydrochemical data interpretation yielded to the achievement of important information that poses the basis for future groundwater protection in an area where main water features were almost unknown.

A Sr0.85Ce0.15FeO3-delta perovskite-type mixed oxide was prepared by solution combustion synthesis from citric acid and carefully characterized for the structure by X-ray diffraction coupled with Rietveld analysis, for the microstructure/morphology by HRTEM and SEM, for texture by N-2 uptake at low temperature, for surface charge by zeta potential measurements and for reactive species by Electron Paramagnetic Resonance (EPR). Photocatalytic activity was tested in the presence of simulated solar light towards Orange II and Rhodamine B as model pollutants. Despite this compound is known as photocatalyst, a good reactivity was evidenced in the 55-80 degrees C temperature range without light irradiation, indicating that it can work as well in the dark after thermal-activation. Therefore, experimental data obtained in this work suggest to carefully reconsidering the role of this mixed oxide as photocatalyst. EPR spin-trapping tests allowed to deepen the aspects related to reactive species generated by Sr0.85Ce0.15FeO3-delta, revealing that the temperature increase promotes hydroxyl radicals and singlet oxygen production. Furthermore, an interesting selectivity towards the degradation of different dyes was found. (C) 2017 Elsevier B.V. All rights reserved.

In this study, bio-based substances (BBS) obtained from composted urban biowaste are used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs). The BBS-stabilized NPs are characterized by means of different techniques (FTIR, XRD, SEM, BET analysis, magnetization curves). Additionally, TGA coupled on-line with FTIR and GC/MS analysis of the exhausted gas are performed in order to simultaneously identify all the degradation products and evaluate the exact composition of such BBS-stabilized materials. Moreover, Fenton-like or photo-Fenton-like experiments carried out at circumneutral pH are performed in order to evaluate the BBS-functionalized NPs photo-activity towards the degradation of caffeine (taken as model emerging pollutant). The obtained promising results encourage the use of BBS as a green alternative tool for the preparation of smart materials with enhanced magnet-sensitive properties, also suitable for applications in wastewater purification treatments., Facultad de Ciencias Exactas, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

This study reports on the use of soluble biobased organic substances (SBO) with emulsifying properties in the production of oil-in-water emulsions for industrial consumption. One of the potentially interesting applications is in formulation of metalworking fluids, which typically consist of oil-in-water emulsions used in metal manufacturing industries. Soluble biobased substances were collected from urban food and gardening wastes in a waste management plant located in a densely populated area in North Italy. The biowastes were fermented under anaerobic and/or aerobic conditions and then treated chemically to yield four different SBO samples, which were characterized for chemical composition, solution behavior by water surface tension measurements, and ability to form stable 10% oil-in-water (O/W) emulsions. Experiments were carried out to evaluate the hydrophilic–lipophilic balance of emulsions with surfactant concentrations in the 2–8% (w/w) range. Stable emulsions were obtained with at least 3% (w/w) s...

International audience; Composts are potential substitutes of mineral fertilizers for sustainable agriculture. Composts are commonly applied to soil at high dose, e.g. from 20 to 30 t (dry matter) per ha and year, to compensate organic matter loss and nutrient depletion. Recently, amendment of soluble substances from urban compost at a much lower dose of 1.55 t per ha enhanced tomato productivity much more than the compost itself. Here, we studied the effect of soluble substances at 0–700 kg per ha on red pepper. We measured productivity, chlorophyll, and soil chemical composition. The most remarkable result is an observed maximum productivity for only 140 kg per ha of compost soluble substances. The increases amounted to 90 % for the precocious crop yield, to 66 % for the total crop production, and to 17 % for the per fruit weight. The discovery that the highest effects occur at such low treatment dose is very promising to enhance crop productivity in a sustainable way. No detectable change of soil chemical composition was observed.

Nitrobenzene thermal degradation was investigated using the Fenton reagent in different experimental conditions. Reaction products were analyzed by HPLC, GC–MS, LC–MS and IC. The products obtained at different nitrobenzene conversion degrees show that degradation mainly involves successive hydroxylation steps of the aromatic ring and its subsequent opening followed by oxidation of corresponding aliphatic compounds. Our results show as primary reaction products: 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, phenol and 1,3-dinitrobenzene, indicating that both hydroxylation and nitration reactions are involved. The formation of phenolic products can be explained by postulating an initial step of HO addition to nitrobenzene ring. The mechanisms of primary reaction pathways are discussed and a detailed kinetic analysis to obtain the true primary yields of phenolic products is proposed. The relative yields observed for nitrophenol isomers do not follow the expected orientation according to deactivating characteristics of the nitro group but significantly depend on Fe+2, Fe+3, H2O2 and O2 concentrations. The understanding of the effect of reaction conditions on the relative product distribution benefits the application of Fenton and Fenton-like systems to waste water treatment.

[EN] The aim of this work is to determine the photostability biocompatibility and efficiency of water soluble bio-based substances (SBO) in photo-oxidative processes for wastewater treatment. Three batches of SBO, isolated from different sources, have been investigated. Differences in the functional groups present in these substances can explain major trends in their physical/chemical properties. Bioassays have proven those materials to be non-toxic but to show poor biodegradability. Their ability to enhance a photo-Fenton process at milder pH (5.2) has been investigated using a mixture of emerging compounds in wastewaters. All the tested SBO were able to remove all pollutants in less than one hour irradiation, and the best results were obtained with those substances showing higher hydrophilic/hydrophobic ratio. Moreover, although SBOs themselves undergo a slight oxidation, no relevant negative effect has been observed for their use in wastewater treatment., The authors want to thank the financial support of the European Union (PIRSES-GA-2010-269128, EnvironBOS) and Spanish Ministerio de Educacion y Ciencia (CTQ2012-38754-C03-02). Juan Gomis would like to thank UPV for his FPI grant (2010-07).

This paper exposes a hydrogeological study of the upper basin of Samala River, one of the main rivers of south western Guatemala flowing into the Pacific Ocean. The objectives of the work are the increase of scientific knowledge about groundwater and their contextualization in terms of socio-economic development. The tectonic and volcanic activity has determined the geomorphology and hydrography of the area and the most common rock types are Cenozoic volcanic rocks and deposits. In correspondence with highland areas the low-permeability bedrock acts as a watershed of groundwater flow, while valleys and calderic depressions are filled by thick layers of permeable pyroclastic materials. These deposits represent the main hydrogeological complex, which hosts an undifferentiated aquifer, only locally confined, where most of the water catchments are located. From a physical-chemical point of view the main parameters of groundwater are within a common value range and the prevalent chemistry is bicarbonate-calcic and magnesiac. The main influencing factors are the nature of the outcropping rocks, the volcanic activity, the chemical modification due to slow circulation in the aquifer and human activities. The analyzed parameters did not show a significant impairment of water resources quality.

For the first time, sustainable LaFeO3 powders were prepared from soluble bio-based substances (SBO) extracted from urban wastes. For the preparation of the perovskite-type powders, a modified solution combustion synthesis route was used, where SBO have the triple role of fuel, complexant and micro-powders, using complementary characterization techniques, evidenced their peculiar microstructural, morphological, textural and photocatalytic properties. Preliminary photodegradation tests of a phenol-based wastewater pollutant and photobleaching of a model dye were performed on the waste-derived and reference LaFeO3 structural templates. A careful examination of the LaFeO3 powders; the obtained results encourage further studies on the application of these materials as heterogeneous catalysts for wastewater treatment. Moreover, a meaningful amount of entrapped matter was evidenced in the powders, which is responsible for most of their peculiar properties.

HPLC/UV–VIS diode array and HPLC/MS techniques were successfully applied to the analysis of sulfonated molecules present in samples coming from the photocatalytic degradation of the azo dye indicator, methyl orange. The substrate was chosen as a simple model for the study of reactions involving the more complex commercial products used for the dyeing of textile fibers. Unexpected MS fragmentation path was observed, due to the very stable methyl orange molecular structure. The chromatographic information were combined with the obtained MS, MS/MS data and the UV–VIS diode array spectra and allowed to rationalize the molecular structures attributable to the various degradation products.

This paper describes the synthesis of paramegnetic iron-containing hydroxyapatite nanoparticles and their increased Cu2+ sorbent capacity when using Ca2+ complexes of soluble bio-organic substrates from urban wastes as synthesis precursors. A thorough characterization of the particles by TEM, XRD, FTIR spectroscopy, specific surface area, TGA, XPS, and DLS, indicates that loss of crystallinity, a higher specific area, an increased surface oxygen content, and formation of surface iron phases strongly enhance Cu2+ adsorption capacity of hydroxyapatite-based materials. However, the major effect of the surface and morphologycal modifications is the size diminution of the aggregates formed in aqueous solutions leading to an increased effective surface available for Cu2+ adsorption. Maximum sorption values of 550-850 mg Cu2+ per gram of particles suspended in an aqueous solution at pH 7 were determined; almost 10 times the maximum values observed for hydroxyapatite nanoparticles suspensions under the same conditions., Facultad de Ciencias Exactas, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

Microwave-assisted micellar extraction (MAME) has been tested for the recovery of polycyclic aromatic hydrocarbons (PAHs) present in samples of marine sediments. An aqueous solution of the nonionic surfactant polyoxyethylene(23)dodecyl ether (Brij 35) was employed as the extracting medium. The proposed approach showed recovery efficiencies comparable to those afforded by the Soxhlet technique with organic solvents, but a neat reduction of the extraction times and a better reproducibility were observed. A MAME-based protocol was successfully applied for the analysis of a certified sample.

The decomposition of naphthalene in the presence of TiO2 dispersions irradiated with simulated solar light has been investigated in water and in aqueous Brij 35 solutions, used to wash soil samples containing the adsorbed pollutant. The monitoring of the reaction system performed during the treatment showed the formation of various aromatic intermediates, in turn degraded, which were identified using suitable analytical techniques. Fast and complete mineralization of naphthalene to CO2 was achieved when working in the absence of additives, whereas a neat inhibition of the degradation was observed in the presence of amphiphiles and other organic components coming from soil. Experimental conditions under which surfactant-containing washes can be treated were investigated and defined.