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Background: No consensus in the literature has been found about the necessity of implementing a decolonization screening protocol for Staphylococcus aureus in patients who undergo prosthesis implantation of the knee (TKA) or of the hip (THA), with the aim of reducing periprosthetic infections (PJIs). Methods: A systematic literature search was conducted using PubMed, Web of Science, and Embase in April 2024. Studies conducted on patients who underwent a TKA or THA and who followed a screening and decolonization protocol from S. aureus were included. The benefits of implementing this protocol were evaluated through the number of infections overall caused by S. aureus and other pathogens. The risk of bias and quality of evidence were assessed using Cochrane guidelines. Results: A total of 922 articles were evaluated, and of these, 12 were included in the study for a total of 56,930 patients. The results of the meta-analysis showed a reduced risk of overall PJI (p = 0.002), PJI caused by S. aureus (p < 0.0001), and PJI caused by MRSA (p < 0.0001) and highlighted no differences between the two groups in the onset of a PJI caused by other bacteria (p = 0.50). Conclusions: This study showed that the screening and decolonization of S. aureus in patients undergoing THA or THA procedures reduced the risk of a PJI. The screening and decolonization protocol for this kind of patient represents an important procedure for the safety of the patient and in social-economic and medico-legal terms. [ABSTRACT FROM AUTHOR]

Nonunion (NU) is one of the most feared complications of femoral shaft fracture treatment. Femoral shaft fracture treatment is often linked with poor bone stock and reduced bone metabolism. In this paper, the goal is to carefully analyze the best treatment options for patients who developed nonunion after the intramedullary nailing of a femoral shaft fracture. A systematic review of the literature available in the PubMed, EMBASE and Cochran library databases was carried out, and 16 studies were included. Exclusion criteria included case reports and case series that do not have data about clinical outcomes or functional outcomes and included fewer than 10 patients. The reviewed data provide evidence for very good results about the treatment of this pathology with exchanging intramedullary nails or the implantation of a plate and screws (general healing rate of 96.3%). Moreover, the data support the utilization of autologous bone graft in order to stimulate the healing process. In conclusion, the choice between these two types of treatment must be guided by the type of pseudarthrosis that the patient presents. Additionally, bone grafting or growth factors promote bone regenerative processes, especially in patients with oligo-atrophic pseudoarthrosis. [ABSTRACT FROM AUTHOR]

• Melamine and s-triazines derivatives are degraded by VUV-photolysis. • Melamine can be mineralized upon VUV-photolysis. • VUV-photolysis and TiO 2 photocatalytic degradation of melamine have been compared. 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 O 2 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 TiO 2 -based photocatalysis. [ABSTRACT FROM AUTHOR]

The ruling n. 38485, 20 June 2019, of the Italian Supreme Court, III criminal section, addressed by the perspective of the law the very sensitive and new issue of telemedicine.This commentary deals with the issue of authorization of telemedicine activities by the health authority, starting from the Italian Court of Criminal Cassation, III section, decision n. 38485/2019. The case law explored the authorization of a health point, which carries out telemedicine services.Starting from the perspective discussed by Italian health regulations, the paper examines how the health act could be defined, with the possibilities offered by telecommunications, and how it now relates legally to the physical place where it takes place.Even if telemedicine opens the way to virtual spaces of health practice, the Ministry of Health Italian Guidelines pose functional and logistical issues to guarantee users’ safety and health care system accountability. Then, functional requirements for health legitimate practice, and their continuous monitoring, together with the responsibilities of the service centers, health professionals and health facilities, are discussed.The questioning of States’ health law, in a broad health system such as that of the Europe, characterized by autonomous health regulations, is extremely important for cross-border health policy with telemedicine, as overall regulatory compliance in health care is the ground criterion for risk prevention and patient safety, to be properly verified. [ABSTRACT FROM AUTHOR]

The removal of hexavalent chromium, Cr(VI), from a water-sediment system has been studied in vitro in different condition of soil water saturation, in order to simulate different possible occurring real scenarios. Two different approaches have been compared: the bio-mediated and the chemical Cr(VI) reduction. In the first technique three organic nutrients have been tested: glucose, trehalose and β-cyclodextrin. For the chemical remediation reducing agents such as sodium sulphite, sodium metabisulphite and ascorbic acid were considered. Both bio-mediated and chemical remediation approach yielded to the total abatement of Cr(VI) from a contaminated soil. No relevant drawbacks were observed in term of release of metal ions in solution or pH perturbation. Among the organic nutrients glucose showed the best performances while the best chemical reducing agent was ascorbic acid. Ascorbic acid can be considered more advantageous because its reaction with Cr(VI) is very fast (total Cr(VI) abatement in 24 h) and allows a better control of the process parameters, not involving the action of microorganisms; moreover its higher cost compared to glucose, is compensated by the much lower amount necessary to attain 100% of Cr(VI) reduction. In case of in-situ remediation of groundwater, the spreading on soil of ascorbic acid would contribute to reduce the leaching of Cr(VI), helping the overall site remediation. [ABSTRACT FROM AUTHOR]

This study reports on the use ofsoluble biobased organic substances(SBO) with emulsifying properties in the production of oil-in-wateremulsions for industrial consumption. One of the potentially interestingapplications is in formulation of metalworking fluids, which typicallyconsist of oil-in-water emulsions used in metal manufacturing industries.Soluble biobased substances were collected from urban food and gardeningwastes in a waste management plant located in a densely populatedarea in North Italy. The biowastes were fermented under anaerobicand/or aerobic conditions and then treated chemically to yield fourdifferent SBO samples, which were characterized for chemical composition,solution behavior by water surface tension measurements, and abilityto form stable 10% oil-in-water (O/W) emulsions. Experiments werecarried out to evaluate the hydrophilic–lipophilic balanceof emulsions with surfactant concentrations in the 2–8% (w/w)range. Stable emulsions were obtained with at least 3% (w/w) surfactantconcentrations. All SBO samples presented the characteristics necessaryfor acting as emulsifiers, when compared with conventional emulsifiers.According to rheology, particle size, and centrifugation tests, SBOsamples isolated from composted biowastes performed better than samplesisolated from the digestate of anaerobically fermented biowastes.The product ash content and/or isolation process also affect the emulsifierperformance. The effects of the biowaste source, chemical composition,and surface activity on the emulsifier performance were evaluated,indicating the feasibility of attaining stable emulsions with environmentalbenefits. [ABSTRACT FROM AUTHOR]

Highlights: [•] Bio-based organic substances (SBO) have been used in photochemical processes. [•] A mixture of six emerging pollutants has been used as target effluent. [•] SBO-mediated reactive species generation cannot compensate for the screen effect. [•] SBO have been demonstrated to enhance mild photo-Fenton (pH=5.2). [Copyright &y& Elsevier]

Photodegradation of anthracene has been studied in aqueous solutions containing soluble bio-organic substances isolated from urban refuse. To perform a preliminary rapid feasibility study of this process while reducing the amount of analytical effort and reagents, an experimental set-up was developed comprising a Teflon coil surrounding a UV-lamp and coupled with an in-line spectrofluorimeter. In this fashion only few millilitres of solution are needed to study the degradation process. Furthermore, the in-line spectroscopic approach enables monitoring of the process without consumption of reagents. Additional studies by liquid chromatography and use of toxicity tests clearly indicated that the apparent inhibition effect of bio-organic compounds on anthracene degradation is not relevant. The results imply that urban refuse may be used as an auxiliary in the recovery of polycyclic aromatic hydrocarbons from contaminated soil by washing, without deleterious effects on the photodegradation of anthracene and other aromatic pollutants. [ABSTRACT FROM AUTHOR]

Abstract: Soluble substances of biological origin (SBO) isolated from urban bio-wastes (UBWs) are shown to be efficient photosensitizers for the abatement of naphthalene sulfonates from aqueous solutions. Depletion of 70–80% of the investigated mono- and disulfonated probe substrates was demonstrated to occur after solutions containing 20mgL−1 probe substrates in the presence of 150mgL−1 SBO were irradiated for 24h. The residual organics in solution did not exhibit any potential acute toxicity. The photodegradation of SBO occurred together with the photodegradation of the probe substrates. The implications of these results for the development of products obtained from UBW are discussed. It would seem that these bio-wastes have greater potential as a renewable, sustainable source of chemical auxiliaries than previous studies have led us to believe. [Copyright &y& Elsevier]

Abstract: To promote bio-based products for the industry, six bio-organic substances (cHALi) isolated from yard trimmings (green) and food (humid) urban residues aged under aerobic digestion for 0–60 days were investigated for their potential to perform as sensitizers for azo-dyes photodegradation. Ethylorange (EO) was used as probe molecule at 5mgL−1 starting concentration and irradiated in a closed Pyrex® cell with a Xenon (1500W) lamp and a cut-off filter for wavelengths below 340nm or in a cylindrical photochemical reactor equipped with a 125W medium pressure Hg lamp. The cHALi/EO ratio in the starting EO solution varied in the 0–200 (w/w) range. The % dye abatement was found a function of the irradiation time, of the type of cHALi substance and of the cHALi/EO ratio. The best results were achieved with cHALi isolated after 7 days biomass aerobic digestion. Total dye abatement was achieved within relatively short few hours. A progressive dye mineralization was observed under the same experimental conditions. On the contrary no significant degradation was evident for the cHALi substances within the same irradiation time. Several hydroxylated azo compounds were identified as likely responsible of residual color after total EO abatement. The results, coupled to the previously reported good performance of the same cHALi substances as auxiliaries for textile dyeing, augur well for the development of both efficient and environmentally friendly textile dyeing processes. [Copyright &y& Elsevier]

Abstract: High-performance liquid chromatography coupled to ultraviolet diode array detection and electrospray ionization mass spectrometry was applied to monitor the photocatalytic degradation mediated by TiO2 of three sulfonated monoazo dyes (Orange I, Orange II, and Ethylorange) present in aqueous solution. Photobleaching, organic carbon, nitrogen and sulfur evolution were also followed during the process. Delayed carbon mineralization was observed with respect to both dyes disappearance and photobleaching, due to the formation of transient intermediate compounds which were in turn completely degraded. Among the intermediates produced during the initial degradation steps the formation of several hydroxylated derivatives, mostly coloured, was evidenced. The MS2 spectra allowed one to formulate hypothesis about the OH attack positions; a peculiar reactivity of the azo moiety was shown by Orange I and Orange II. [Copyright &y& Elsevier]

The effect of sodium dodecyl sulphate (SDS) on the photocatalytic degradation of 2,4,5-trichlorophenol (2,4,5-TCP) in aqueous TiO2 dispersions under irradiation with simulated AM1 solar light was investigated. A peculiar kinetic behaviour was observed, with increasing inhibition of the substrate degradation as a function of SDS concentration below the critical micellar concentration (cmc), followed by a subsequent faster degradation around this concentration range and a further degradation rate decrease above the cmc. The role of surfactant adsorption onto the suspended semiconductor and the disaggregation of TiO2 microparticles seems to be crucial. The complete degradation of the investigated substrate, still achievable in the presence of SDS without relevant changes in the reaction mechanism, was confirmed suggesting the possible application of photocatalysis for the treatment of surfactant-containing wastes. [Copyright &y& Elsevier]

The photocatalytic oxidation of acetonitrile (CH3CN) was carried out in aqueous suspensions of polycrystalline TiO2 P25 Degussa irradiated by sunlight. A plug flow photoreactor in a total recycle loop was used for carrying out reactivity experiments in which the concentrations of acetonitrile, of its intermediate oxidation products and of not-purgeable organic carbon (NPOC) were monitored. The influence of the presence of strong oxidant species (H2O2, S2O82−, ClO−) on the process rate was studied. The dependence of acetonitrile photo-oxidation rate on the substrate concentration and on the catalyst amount was also investigated. The photodegradation rate of substrate and NPOC followed first order kinetics with respect to acetonitrile and NPOC concentrations, respectively. The presence of S2O82− and solar irradiation determined the occurrence of homogeneous degradation of acetonitrile and NPOC. In the presence of irradiated catalyst, a significant synergetic effect was observed for NPOC degradation while for the acetonitrile oxidation this effect was not evident. H2O2 did not affect the process while ClO− affected negatively the acetonitrile oxidation rate and it inhibited the NPOC degradation. [Copyright &y& Elsevier]

The degradation of Methyl Orange (C14H14N3SO3Na), chosen as a model sulfonated azo dye, was investigated in aqueous solutions containing suspended polycrystalline TiO2 particles under irradiation with simulated sunlight. The dye disappearance and the formation of the mineralization end products were monitored; the formation of the main transient intermediates was also examined in detail. Particular attention was devoted to the identification and to the evolution of fragments retaining the chromophoric group. The comparison of data coming from various analytical techniques led to a possible reaction mechanism for the degradation process, giving insight into an aspect of the treatment which has not been considered in previous studies. [ABSTRACT FROM AUTHOR]

A procedure to extract polycyclic aromatic hydrocarbons (PAHs) from a contaminated river sediment is discussed; this combines short extraction times obtained by microwave energy with the peculiar solvent capability of aqueous micellar solutions. The technique, named microwave-assisted micellar extraction (MAME), was tested for the extraction of 11 PAHs from a spiked river sediment using polyoxyethylene (23) dodecyl ether (Brij 35), polyoxyethylene (10) dodecyl ether (C 12 E 10 ) or cetyl trimethylammonium bromide (CTAB). Different temperatures and extraction times were explored to establish whether this method has merit. Comparative measurements were made using sonication and Soxhlet extraction with acetone-hexane. Generally, Soxhlet extraction was revealed to be the most effective method to extract the PAHs from the solid matrix, with percent of recovery ranging from 92% to 102%. Nevertheless, high recoveries were also achieved by MAME using C 12 E 10 ; in fact, with only the exception of indeno[1,2,3- cd ]pyrene, the differences between recoveries obtained by MAME and Soxhlet extractions were below 10% for all the considered compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advanced oxidation processes need a careful analytical control. • Performance and limits of different analytical approaches have been compared. • Chemometric tools improve information provided by UV and fluorescence spectroscopy. • Surrogate methods are suitable for real-time, inline process monitoring. • Traditional and surrogate methods are complementary for in depth AOP control. 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-H 2 O 2 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. [ABSTRACT FROM AUTHOR]

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 °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. [ABSTRACT FROM AUTHOR]

The exploitation of organic waste as a source of bio-based substances to be used in environmental applications is gaining increasing interest. In the present research, compost-derived bio-based substances (BBS-Cs) were used to prepare hybrid magnetic nanoparticles (HMNPs) to be tested as an auxiliary in advanced oxidation processes. Hybrid magnetic nanoparticles can be indeed recovered at the end of the treatment and re-used in further water purification cycles. The research aimed to give new insights on the photodegradation of caffeine, chosen as marker of anthropogenic pollution in natural waters, and representative of the contaminants of emerging concern (CECs). Hybrid magnetic nanoparticles were synthetized starting from Fe(II) and Fe(III) salts and BBS-C aqueous solution, in alkali medium, via co-precipitation. Hybrid magnetic nanoparticles were characterized via X-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The effect of pH, added hydrogen peroxide, and dissolved oxygen on caffeine photodegradation in the presence of HMNPs was assessed. The results allow for the hypothesis that caffeine abatement can be obtained in the presence of HMNPs and hydrogen peroxide through a heterogeneous photo-Fenton mechanism. The role of hydroxyl radicals in the process was assessed examining the effect of a selective hydroxyl radical scavenger on the caffeine degradation kinetic. [ABSTRACT FROM AUTHOR]

Sustainable alternative substrates for advanced applications represent an increasing field of research that attracts the attention of worldwide experts (in accordance with green chemistry principles). In this context, bio-based substances (BBS) isolated from urban composted biowaste were purified and characterized. Additionally, these materials were tested as auxiliaries in advanced oxidizing photocatalytic processes for the abatement of organic contaminants in aqueous medium. Results highlighted the capability of these substances to enhance efficiency in water remediation treatments under mild conditions, favoring the entire light-driven photocatalytic process. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The effect of the synthesis and processing parameters on the thermocatalytic performance of Ce-doped SrFeO3 inorganic perovskites was investigated to improve the reproducibility and reliability of the synthetic methodology and of the testing procedure. A structural, surface and redox characterization was performed to check the extent of variability in the chemical–physical properties of the prepared materials, revealing that a strict control of the synthesis parameters is indeed crucial to optimize the thermocatalytic properties of Ce-doped SrFeO3 inorganic perovskites. The thermocatalytic tests, aimed to degrade organic pollutants in water, were performed using Orange II and Bisphenol A as target compounds, in view of a later technological application. The main issues in the synthesis and testing of Ce-doped SrFeO3 perovskite thermocatalysts are highlighted and described, giving specific instructions for the resolution of each of them. A limited number of prepared materials showed an efficient thermocatalytic effect, indicating that a full gelification of the sol, an overstoichiometric reducer-to-oxidizer ratio, a nominal cerium content of 15 mol%, slightly higher than its solubility limit (i.e., 14 mol%), a pH of 6 and a thermal treatment at 800 °C/2 h are the best synthesis conditions to obtain an effective Ce-doped SrFeO3 perovskite. Regarding the testing conditions, the best procedure is to follow the degradation reaction without any preconditioning with the pollutant at room temperature. The severe leaching of the active perovskite phase during tests conducted at acidic pH is discussed. Briefly, we suggest confining the application of these materials to a limited pH range. Variability between thermocatalysts prepared in two different laboratories was also checked. The issues discussed and the proposed solutions overcome some of the obstacles to achieving a successful scale up of the synthesis process. Our results were favorable in comparison to those in the literature, and our approach can be successfully extended to other perovskite catalysts. [ABSTRACT FROM AUTHOR]

Pseudarthrosis (PSA) is a possible complication of femoral shaft fracture treatment. It is often associated with reduced bone quality and can, therefore, adversely affect quality of life. Its treatment poses a major challenge for orthopaedic surgeons. Several authors have set forth different surgical approaches for the treatment of pseudarthrosis, such as internal fixation with plate and screws, replacement of an intramedullary nail or prosthetic replacement. In cases associated with bone loss, osteopenia, or comminution of fracture fragments, autologous or homologous bone grafts may also be used. The chronic outcomes of the surgical treatment of femoral shaft pseudarthrosis, even when consolidation is achieved, are linked to disabling sequelae of clinical-functional relevance, deserving an adequate medico-legal evaluation. The purpose of this retrospective study is to analyse a clinical case series of patients treated for atrophic femoral shaft pseudarthrosis at the IRCCS Orthopaedic Institute Galeazzi, Milan, Italy, from 2014 to 2020 and their orthopaedic-traumatological and medico-legal implications. [ABSTRACT FROM AUTHOR]

Waste-derived, soluble bio-based substances (SBO), are effective low-cost photosensitizers that could find application in pollutant photodegradation. For this reason, it is important to understand if and to what extent irradiation could modify their properties. The exposure of SBO to simulated sunlight induced important spectral and structural modifications. Both the whole material and its acid-soluble fraction were characterized, highlighting several properties in common with humic and fulvic substances, including absorption spectra, specific absorbance and fluorescence behavior. The latter was described with a three-component model using PARAFAC analysis. Irradiation induced SBO photobleaching, but the absorbance of the acid-soluble fraction increased with irradiation. This finding suggests a progressive photochemical solubilization of SBO, which is confirmed by the increase of the carboxylic groups. In addition to absorbance, the fluorescence of whole SBO was also decreased by irradiation, thereby suggesting that both chromophores and fluorophores were photodegraded. The increasingly hydrophilic character given to SBO by irradiation also accounted for the photoinduced decrease of the surfactant properties of the material. [ABSTRACT FROM AUTHOR]

The assessment of environmental sustainability has assumed great importance during the study and implementation of a new process, including those aimed to waste valorization and reuse. In this research, the environmental performance of the photo-Fenton processes was evaluated using the life cycle assessment (LCA) methodology. In particular, photo-Fenton conducted in mild conditions (almost neutral pH), using soluble bio-organic substances as auxiliary agents were compared with the "classic" photo-Fenton run at pH 2.8. The evaluation was carried out both, at the laboratory level and at pilot plant scale. LCA analysis shows that working in mild conditions reduces the environmental burden associated with the use of chemicals. On the other hand, the occurring drop in effectiveness significantly increases the overall impact, thus evidencing the need of considering the process as a whole. [ABSTRACT FROM AUTHOR]

A cheap and easy to use Arduino self-assembled automatic system was employed to continuously monitor the hydrogen peroxide consumption during the photo-Fenton degradation of caffeine, selected as model target compound. The automatic system made it possible to measure the H 2 O 2 concentration in the reaction cell via a colorimetric reaction and to take samples for HPLC analysis minimising the operator manual intervention and exposure to UV radiation. The obtained results were compared in terms of LOD and LOQ with H 2 O 2 measurements manually performed using UV–Vis spectrophotometry, evidencing better analytical performance when using the automatic system; LOD and LOQ were respectively 0.032 mM and 0.106 mM for the automatic system against 0.064 mM and 0.213 mM for UV–Vis spectrophotometry. Furthermore, the photo-Fenton treatment was optimised by means of a Design of Experiments (DoE) investigating the effect of added H 2 O 2 concentration, iron concentration and caffeine initial concentration on system performances. The use of the automatic device for such monitoring provided several advantages: automation (with consequent reduction of the workload), measurement increased precision, reduced reagents consumption and waste production in agreement with the principles of Green Analytical Chemistry. [Display omitted] • An automatic system enabled H 2 O 2 quantification & minimized manual intervention. • The automatic measurement showed lower LOD & LOQ than the traditional method. • DoE combined with automatic device allows photo-Fenton treatment optimization. • New device offers automation, precision, reduced workload & operator exposure. • Study showcases automatic devices potential in laboratory analyses. [ABSTRACT FROM AUTHOR]

Abstract: Reactive dyes are widely employed in textile industries and their removal from wastewaters is a relevant environmental problem. In addition to chemical and physical methods, several bioremediation approaches, involving intact micro-organisms or isolated enzymes, have been proposed to decolorize dye solutions. In this paper, we report the complete and fast decolourization of a Cu(II)-phthalocyanine based reactive dye (Remazol Turquoise Blue G 133) by means of the soybean peroxidase/H2O2 system. The oxidative degradation of the dye in aqueous solution at 25°C was studied as function of pH, revealing a quantitative decolourization yield at acidic pH values with a maximum of activity at pH 3.3. The reaction products were identified and characterized by HPLC–diode array detector (DAD)–mass spectrometry (MS), ionic chromatography and EPR techniques. This analysis showed that the enzyme catalyses the breaking of the phthalocyanine ring producing sulfophthalimide as the main degradation product, and the release of stoichiometric amount of ammonium and Cu(II) ions. [ABSTRACT FROM AUTHOR]

Presents a study which examined the photodegradation of two common azo-dyes in aqueous suspension of titanium oxide under solar irradiation. Methods; Results; Discussion.

• The effect of HA coating on MPs was studied in photo-Fenton-like process. • Humic acid coating enhances the H 2 O 2 and S 2 O 8 2− activation for BPA degradation. • Reactive species were identified (OH and SO 4 –) through scavenging experiments. • The recycling and reuse of MP/HA show no loss of activity. • The efficiency of MP/HA was tested in real wastewater sample. 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. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants have been increasingly detected in natural waters, and this represents a real challenge to the quality of this resource. To remove these species, advanced treatment technologies are required. Among these technologies, Fenton-like and photo-Fenton-like processes have been investigated for the removal of pollutants from water. Delicate aspects of photo-Fenton processes are that light-driven processes are energy intensive and require a fair amount of chemical inputs, which strongly affects their overall environmental burdens. At present, aside from determining the efficiency of the processes to remove pollutants of a particular technology, it becomes fundamental to assess also the environmental sustainability of the overall process. In this work, the methodology of the life cycle assessment (LCA) was applied to identify the hotspots of using magnetite particles covered with humic acid (Fe3O4/HA) as a heterogeneous photo-Fenton catalyst for water remediation. The sustainability of the overall process was considered, and a comparative LCA study was performed between H2O2 and persulfate activation at different pH. The addition of humic substances to the particles allows the effectiveness of the catalyst to improve without increasing the environmental impacts; these processes are strongly correlated with energy consumption and therefore with the efficiency of the process. For this reason, working at acidic pH allows us to contain the impacts. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Photocatalytic efficiency of ZnO is improved by iron doping. • New materials have been synthesized using different synthetic strategies. • The best performances were obtained using the hydrothermal process. • Phenol and Ketoprofen abatement are favoured with ZnO doped with iron at 0.5%. • Ketoprofen and its byproducts were successful abated also in a real wastewater. Abstract This study aims to investigate how the photocatalytic efficiency of zinc oxide can be improved by introducing doping species into its crystal lattice. New materials based on zinc oxide doped with iron, have been synthesized using different methods, characterized and tested toward the abatement of selected organic molecules. The different synthetic strategies followed comprised sol-gel, precipitation and hydrothermal processes, in order to identify which one is capable of guaranteeing the best photocatalytic performances. The photoactivity of the new semiconductors was firstly tested using phenol as a model molecule subjected to irradiation under UV-A light. Phenol abatement is particularly favoured when using ZnO prepared via hydrothermal method and doped with iron at 0.5%. These materials were then tested toward the elimination of ketoprofen, an emerging pollutant substance, from water and real wastewater. Ketoprofen and its transformation products are completely abated within 30 min in pure water or in 1 h in wastewater. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The photodegradation of four micro-contaminants has been studied. • Hybrid magnetic materials have been employed in photo-Fenton like process. • TiO 2 homemade shown better performances than P25. • Micro-contaminants degradation has been attained under solar irradiation. Abstract This work reports on the light-induced heterogeneous photodegradation of four micro-contaminants (MCs): Carbamazepine (C), Flumequine (F), Ibuprofen (I), and Sulfamethoxazole (S), using two different heterogeneous advanced oxidation processes. The first one is the semiconductor photocatalysis, run in the presence of the suspension of a home prepared TiO 2 (TiO 2 HP); the second one is an heterogeneous photo-Fenton process run in the presence of a hybrid magnetic nanomaterial (MB3) with an iron oxides core and an organic shell made of bio-based substances (BBS) isolated from urban biowaste. The two materials work upon two different mechanisms and were already tested (and the action mechanism hypothesized) at the lab scale under model conditions: TiO 2 acts as photocatalyst through the photo-generation of hole/electron pairs able to give rise to oxidation and reduction reactions, whereas hybrid magnetic nanomaterial acts in the presence of H 2 O 2 by a photo-Fenton like mechanism. The results evidenced the better performances of TiO 2 HP (also better than the well-known reference TiO 2 P25). Preliminary photodegradation experiments carried out in a pilot plant under natural solar radiation confirmed the good results obtained with TiO 2 HP. Moreover, in the adopted experimental conditions, the Fe(II) leached from MB3 can be considered as responsible of the MCs degradation through a homogeneous photo-Fenton reaction, where MB3 act as iron reservoir. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (Samalà 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. [ABSTRACT FROM AUTHOR]

A Sr 0.85 Ce 0.15 FeO 3-δ 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 ζ 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 °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 Sr 0.85 Ce 0.15 FeO 3-δ , revealing that the temperature increase promotes hydroxyl radicals and singlet oxygen production. Furthermore, an interesting selectivity towards the degradation of different dyes was found. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: Soluble bio-organic substances (SBO) isolated from urban biorefuses have been investigated in photocatalytic processes for wastewater treatment using a cationic dye, namely crystal violet (CV) as target compound. The SBO have been found to enhance the photobleaching of CV solutions with an optimal SBO concentration of ca. 20mgL−1. Mechanistic investigation based on chemical probes and changes in the absorption spectrum of CV in the presence of SBO seems to indicate that a complex formed between sensitizer and substrate plays a major role in the process. SBO have also been tested for the implementation of photo-Fenton processes at circumneutral media: the observed pseudo first order rate constants for CV decoloration was higher for UV/SBO/Fe(II)/H2O2 (5.5×10−3 min−1) than for UV/Fe(II)/H2O2 (1.5×10−3 min−1). A modified mechanism, in which HO are less relevant that at the acidic medium, is in agreement with results of experiments carried out with chemical probes. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

Abstract: Three alkylpolyoxyethylene surfactants bearing the same hydrophobic chain and a different number of oxyethylene groups were investigated as suitable candidates for the soil washing treatment of contaminated soil samples containing bentazone. Comparable good recoveries of the pesticide were obtained working with these surfactants. The photocatalytic treatment of the collected washing wastes, performed in the presence of suspended TiO2 particles under irradiation with simulated sunlight, leads to the effective degradation of bentazone residues after a time depending on the nature and concentration of the chosen amphiphile. Brij 35 was found to be the best surfactant candidate, giving the faster abatement of the pesticide in the collected wastes. The overall treatment time depends on the bentazone mineralization kinetics, markedly slow in the presence of surfactants. Useful information about the photocatalytic degradation route was obtained from the HPLC–MS analysis of transient intermediates formed in water. [Copyright &y& Elsevier]

Abstract: The effect of simulated solar light on nitrobenzene degradation in Fe3+/H2O2 solutions was investigated under different experimental conditions. Consumption profiles of NBE and H2O2 display an autocatalytic kinetic behavior for both dark and photo-assisted degradation experiments. The rates of the initial slow phase that precedes the catalytic phase are significantly enhanced by irradiation, although the effect of simulated solar light on the rates of the fast phase is negligible. The absolute rates of the slow phase increase with the concentrations of Fe3+ and H2O2, whereas the initial rate of the degree of conversion increase decreases with organic matter loading. The reaction progress was characterized by HPLC, GC–MS, IC, TOC (total organic carbon) and toxicity analyses. The main products detected were 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, 1,3-dinitrobenzene, phenol, oxalic acid, formic acid, NO2 − and NO3 −. Product distribution profiles are discussed in connection with TOC and toxicity measurements. The results show that dark treatment is neither capable of lowering the organic content nor capable of reducing the effluent toxicity to acceptable levels. On the other hand, photo-assisted processes induced by simulated solar light can significantly enhance both mineralization and detoxification efficiencies. [Copyright &y& Elsevier]

The Lab4treat experience has been developed to demonstrate the use of magnetic materials in environmental applications. It was projected in the frame of the European project Mat4Treat, and it was tested several times in front of different audiences ranging from school students to the general public in training and/or divulgation events. The experience lends itself to discuss several aspects of actuality, physics and chemistry, which can be explained by modulating the discussion depth level, in order to meet the interests of younger or more experienced people and expand their knowledge. The topic is relevant, dealing with the recycling of urban waste and water depollution. The paper is placed within the field of water treatment for contaminant removal; therefore, a rich collection of recent (and less recent) papers dealing with magnetic materials and environmental issues is described in the Introduction section. In addition, the paper contains a detailed description of the experiment and a list of the possible topics which can be developed during the activity. The experimental approach makes the comprehension of scientific phenomena effective, and, from this perspective, the paper can be considered to be an example of interactive teaching. [ABSTRACT FROM AUTHOR]

• The effect of HA coating on MPs was studied in (photo)-Fenton-like process. • XPS allowed to relate iron surface speciation with (photo)-Fenton reactivity. • Humic acid coating enhances the catalytic efficiency for 4-CP degradation. • The efficiency of MP/HA was tested by degrading CECs in real wastewater sample. Heterogeneous photo-Fenton reaction with iron-based magnetic materials has been proposed as an alternative to the homogeneous Fenton process to remove contaminants of emerging concern (CECs) because of the low cost, facile recovery and reuse. The iron-based material is not only a reservoir to maintain an effective concentration of iron in solution, but it also activates H 2 O 2 at the surface. Magnetic particles (MPs) coated with different amount of humic acid (HA), prepared by co-precipitation method under anoxic and oxygenated conditions were synthesized. Their features were characterized by different techniques (XPS, XRD, TGA, SEM and FTIR). The ability of those materials to promote Fenton and photo-Fenton-like processes was investigated using 4-chlorophenol as standard substrate. The HA coating increased the catalyst efficiency, both in the dark and under irradiation, showing the best performance at pH below 4 under simulated sunlight. The iron speciation at the MPs surface had a paramount role in the H 2 O 2 (photo)activation, although the processes promoted by the released iron in solution were not negligible on the overall degradation process. It was demonstrated a role of the surface defectivity to promote faster degradations as a consequence of not only a faster photodissolution, but also a higher heterogeneous reactivity promoted by defective sites. The best performing MPs/HA showed high efficiency for the abatement of CECs, namely Carbamazepine, Ibuprofen, Bisphenol A and 5-Tolylbenzotriazole also in real wastewater. The obtained results demonstrated the potential application of the heterogeneous (photo)-Fenton process activated by these inexpensive and environmental friendly materials in advanced wastewater treatments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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–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–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–BBS Fenton-like reaction were obtained. [ABSTRACT FROM AUTHOR]

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® 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]