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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]

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]

Background and purpose: Surfactant-assisted soil washing and photocatalysis are well-known remediation processes of environmental concern. The application of photocatalysis to treat soil washing extracts containing 4-methylphenol, 4-ethylphenol and 4-tert-butylphenol in the presence of nonionic (CE and CE) and anionic (SDS) surfactants and some of their binary mixtures was investigated in this work by studying the pollutants degradation in the presence of TiO dispersions irradiated with simulated solar light. Materials and methods: Clean soil samples were spiked with the investigated alkylphenols. Aqueous solutions of the chosen surfactants were placed in contact for some hours with the spiked soil samples in a rotatory mixer. The pollutants recoveries were evaluated via HPLC analysis. Photocatalytic experiments were performed in solarbox on aqueous solutions and on aqueous surfactant solutions containing the pollutants. Results: The pollutants removal from the soil was proven effective using the examined surfactant solutions. The photocatalytic treatment of the wastes was faster using Brij 35, but also SDS and CE-SDS mixtures can be applied. After 2-5 h the complete pollutants abatement was obtained, depending on the surfactant chosen and on the amount of TiO employed. On the contrary, the treatment of wastes containing CE was an extremely slow process. Conclusions: The photocatalytic approach can be applied to remove the examined aromatic pollutants from the washing wastes, confirming the viable coupling between this advanced oxidation method and the surfactant-based soil remediation treatments. Surfactant adsorption onto TiO and micelles concentration play a dominant role. [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 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]

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]