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Aquaculture and waste valorization have the potential to show solid achievements toward food security and improvements in the circularity of resources, which are crucial aspects of achieving a sustainable lifestyle in agreeance with Agenda 2030 goals. This study aims to optimize and simplify the decision-making processes for the valorization of marine wastes (natural and from aquaculture) as secondary raw materials to produce high-value-added market goods. However, significant concentrations of pollutants may be present within wastes, compromising overall quality, and social dynamics can hinder their usage further. Goro's lagoon was chosen as a case study, where the relations between the ecosystem services, a thriving bivalve economy, and social dynamics are deeply rooted and intertwined. Therefore, in the manuscript cost–benefit and foresight analyses are conducted to determine the best usage for algal biomass considering pollution, social acceptance, and profitability. These analyses are virtually conducted on bio-refineries that could be operating in the case study's area: briefly, for a thirty-year running bio-plant, the CBA indicates the two best alternatives with an income of 5 billion euros (NPV, with a 5% discount rate) for a biofuel-only production facility, and a half for a multiproduct one, leading to the conclusion that the first is the best alternative. The foresight, instead, suggests a more cautious approach by considering external factors such as the environment and local inhabitants. Hence, the main innovation of this work consists of the decision-maker's holistic enlightenment toward the complexities and the hidden threats bound to this kind of closed-loop efficiency-boosting process, which eventually leads to optimized decision-making processes. [ABSTRACT FROM AUTHOR]

In this work a capillary electrophoretic (CE) method is used for the kinetic study of the intermetallic substitutions in hexameric ions of two strategic metals, tantalum and niobium in an alkaline medium. Recently proposed processes for the production and analytical separation of tantalum and niobium that are faster, more economical and environmental friendly are based on the use of highly alkaline media. It was previously established that in these media, tantalum and niobium exist as hexameric species, HxTa6O19X-8 (Ta6) and HxNb6019x-8 (Nb6), which can be analysed with a CE method using an alkaline electrolyte and UV detection. However, when using the above method on an industrial sample a minor species that should correspond to the substituted Ta1Nb5 form was observed. The purpose of the present study is to probe, by means of CE, the kinetic of the formation of substituted niobate-tantalate ions, Ta6-xNbx (1 ≤ x ≤ 5), starting from mixtures of pure hexaniobate and hexatantalate ions. This study required the development of a new CE method allowing the separation of all the five substituted ions and their two non-substituted hexameric parent ions in less than seven minutes. In details, a previously developed separation method was transferred to a Beckman instrument and the separation improved by adjusting the total length, the applied voltage, the injection volume, the rinsing steps and the internal standard. The kinetic study shows that samples initially containing non-substituted hexameric forms of tantalum and niobium in a 1:1M ratio naturally form the five possible substituted species Ta6-xNbx (1 ≤ x ≤ 5) after only a few hours which may represent an issue for future Nb-Ta separation processes operated in alkaline media. The developed method was also transferred to an Agilent instrument and the kinetic study repeated. Results obtained with the Agilent instrument corroborate those obtained with the Beckman instrument. The proposed electrophoretic separation method lays the ground for new analytical techniques that could help assessing the presence of substituted species that can be deleterious for Nb-Ta purification processes.

Contamination by pharmaceuticals adversely affects the quality of natural water, causing environmental and health concerns. In this study, target drugs (oxazepam, OZ, 17-α-ethinylestradiol, EE2, and drospirenone, DRO), which have been extensively detected in the effluents of WWTPs over the past decades, were selected. We report here a new photoactive system, operating under visible light, capable of degrading EE2, OZ and DRO in water. The photocatalytic system comprised glass spheres coated with nanostructured, solvothermally treated WO3 that improves the ease of handling of the photocatalyst and allows for the implementation of a continuous flow process. The photocatalytic system based on solvothermal WO3 shows much better results in terms of photocurrent generation and photocatalyst stability with respect to state-of-the-art WO3 nanoparticles. Results herein obtained demonstrate that the proposed flow system is a promising prototype for enhanced contaminant degradation exploiting advanced oxidation processes. [ABSTRACT FROM AUTHOR]

Plastics and related contaminants (including microplastics; MPs and nanoplastics; NPs) have become a serious global safety issue due to their overuse in many products and applications and their inadequate management, leading to possible leakage into the environment and eventually to the food chain and humans. There is a growing literature reporting on the occurrence of plastics, (MPs and NPs) in both marine and terrestrial organisms, with many indications about the harmful impact of these contaminants on plants and animals, as well as potential human health risks. The presence of MPs and NPs in many foods and beverages including seafood (especially finfish, crustaceans, bivalves, and cephalopods), fruits, vegetables, milk, wine and beer, meat, and table salts, has become popular research areas in recent years. Detection, identification, and quantification of MPs and NPs have been widely investigated using a wide range of traditional methods, such as visual and optical methods, scanning electron microscopy, and gas chromatography-mass spectrometry, but these methods are burdened with a number of limitations. In contrast, spectroscopic techniques, especially Fourier-transform infrared spectroscopy and Raman spectroscopy, and other emerging techniques, such as hyperspectral imaging are increasingly being applied due to their potential to enable rapid, non-destructive, and high-throughput analysis. Despite huge research efforts, there is still an overarching need to develop reliable analytical techniques with low cost and high efficiency. Mitigation of plastic pollution requires establishing standard and harmonized methods, adopting holistic approaches, and raising awareness and engaging the public and policymakers. Therefore, this chapter focuses mainly on identification and quantification techniques of MPs and NPs in different food matrices (mostly seafood). [ABSTRACT FROM AUTHOR]