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Metal nanoparticles (MNPs) have gained significant attention due to their multifunctional properties and broad applications in various fields. In this study, we present a novel and sustainable approach for the synthesis of silver nanoparticles (AgNPs) using waste materials, dried banana pith extract (BPE) and rice water. The synthesised AgNPs exhibit a size of 43 nm and zeta potential of −24.1 mV. A maximum temperature rise of 4°C with an efficiency of 41% is achieved within a short time by the photothermal activity. The qualitative colorimetric detection of Fe3+ and its quantitative spectroscopic detection are achieved in a linear detection range of 20–80 μM and with a limit of detection of 8.5 μM. The sensing mechanism is explained in terms of cooperative binding of Fe3+ ions to BPE-AgNPs. A homogeneous, flexible and stable AgNP-rice starch gel is formed. The work offers environmentally conscious nanomaterials for diverse applications. [ABSTRACT FROM AUTHOR]

In response to the growing consumer focus on healthy, balanced diets, demand for functional foods and products for special nutrition, particularly those enriched with proteins, has significantly increased. Bio-processed marine products have emerged as alternative nutrient sources with potential benefits for consumer well-being. Among these, seafood proteins are especially promising due to their functional properties, including water and oil retention, film formation, emulsification, solubility, and gelling capacities. Recent research highlights the unique roles of various classes of seafood proteins derived from by-products and side-streams as functional ingredients in developing novel protein-enriched foods and in drug delivery. In this framework this review aims to explore eco-innovative extraction technologies and functional properties of native seafood proteins and hydrolysates derived from discarded raw materials, focusing on their applications as bioactive compounds in the development of both protein-enriched foods and biomedical products. Key research findings in these areas are summarized, emphasizing the need for further studies in the fields of chemical engineering, food and biomedical sciences. Finally, this work aims to draw the attention of researchers and industry professionals to advance a comprehensive understanding of seafood protein circular bioeconomy and enhance their use in food and medical applications. • The demand of functional foods, such as protein-enriched foods, has increased • Fish and seafood processing by-products may be a precious source of proteins • The latest techniques for the extraction of seafood-derived proteins were highlighted • Technological and functional properties of seafood proteins were discussed • Seafood-derived protein applications in biomedical and food systems were critically reviewed. [ABSTRACT FROM AUTHOR]

Ocean plastic waste poses a growing environmental threat, efforts are now underway to help clean the ocean surface or to prevent plastic streams entering. Repurposing these highly mixed polymers presents a great challenge due to their inherent complexity, intertanglement, and the presence of contaminants. Herein, we process real samples of ocean-floating plastics from the North Pacific Garage Patch through supercritical hydrothermal liquefaction (HTL), targeting their chemical recycling into synthetic crude oil. Investigating key process parameters (temperature, pressure, time, and plastic load), we found that plastic load and temperature are crucial parameters influencing oil yield and that moderate conditions maximized hydrocarbon yield, reaching 90 wt%. Overall, longer residence times and higher temperatures favored aromatic-rich oils. We suggest a reaction pathway to account for hydrogen release from aromatization reactions, influencing paraffin, olefin, and aromatic contents. Supercritical HTL offers an effective, tailored approach for recycling complex plastic mixtures to produce synthetic crude oil. [Display omitted] [ABSTRACT FROM AUTHOR]

Global alumina production generates approximately 150–170 million tonnes of bauxite residue (BR), predominately landfilled. The cement industry is looking for new supplementary cementitious materials (SCMs) to replace additional clinker volumes and reduce their carbon footprint. Symbiosis between the alumina and cement industries presents an opportunity to conserve resources and produce low-carbon cements by thermally modifying BR into novel SCMs. This research uses the Horizon 2020 ReActiv project as a case study to evaluate the suitability of different modified BRs for use as SCMs using evidence from project documentation and participant observations from progress meetings. It also explores symbiotic business model configurations between alumina and cement industries through semi-structured interviews with ReActiv project participants. Results indicate that thermal modification of BR significantly increases its cementitious value, and should optimally be carried out in alumina plants, with the cement industry then grinding and mixing the resulting SCM with other cement components. [Display omitted] [ABSTRACT FROM AUTHOR]

This work studies an innovative approach to water treatment by using recycled electric induction furnace slag for the removal of Cd, Cr and Pb-ions and comparing the results to a treatment with specifically developed CeO 2 nanoparticles. The slag was characterised by X-ray Fluorescence, X-ray diffraction and SEM. The effects of initial ion concentration and adsorbent dose were investigated according to an experimental design. Adsorption tests were carried out with ion solutions present in concentrations ranging from 1 to 10 mg/L and adsorbent doses from 0.064 to 0.64 g/L. The removal mechanism for CeO2 is adsorption. For slag, literature proposes a mechanism involving chemical adsorption of Cd2+, Cr6+ and Pb2+ by silanol and aluminol groups; precipitation in the form of metal silicates formed between the cations and silicic acid leached from the slag provides an alternative explanation. The removal efficiencies with nanoparticles are higher than reported for any other adsorbent (including slag) under all test combinations for the three metals investigated. The maximum removal efficiency with slag was 74% for Cr6+, 64% for Cd2+ and 34% for Pb2+, comparable to, or higher than, other materials reported in literature. The treatment with slag has clear promises in terms of economy and scalability. [ABSTRACT FROM AUTHOR]

• Breweries generate large quantities of waste materials per litre of beer produced. • LCA is used to model current management and valorisation of barley straw. • The valorisation scenario has a higher environmental impact associated. • This impact is mainly caused by the high energy use in the extraction process. Most food manufacturers in industrialised countries produce significant amounts of food wastes during their manufacturing activities. Due to the serious environmental consequences of managing these materials, environmental impact analyses have become popular to identify more sustainable practices for food waste management. Life-Cycle Assessment (LCA) is a useful methodology to assess such environmental impacts. This paper presents the main results obtained using the LCA methodology to analyse the potential environmental impacts of waste management for a brewery in the UK. Initially, the main waste types are identified for this industry: barley straw, malt waste and spent grain, and then barley straw is selected to study its environmental impact in detail. An alternative, more sustainable way to manage barley straw by extracting its wax with supercritical CO 2 is discussed. SimaPro software is used to both quantify potential environmental impacts and evaluate the overall environmental performance of this valorisation opportunity, and to compare its modelled environmental impacts to the current impacts of managing barley straw. Results show that valorising barley straw by this method generates a high environmental impact due to the energy requirements of the processes involved, principally for human toxicity (cancer effects), human toxicity (non-cancer effects) and freshwater ecotoxicity impact categories. Using more energy-efficient processes or an alternative energy source would reduce this environmental impact. The analysis used in this paper allows an objective comparison between different scenarios with the final aim of supporting the use of sustainable solutions for waste management in the food industry. [ABSTRACT FROM AUTHOR]

Water contamination caused by anthropogenic, and unforecasted release of BTEX (benzene, toluene, ethylbenzene and xylene) compounds threatens the quality and integrity of aquatic ecosystems. BTEX sorption with novel materials characterized by increased hydrophobicity and stability has been proposed to overcome such contamination. This study aimed to investigate the whole array of hydrothermally synthesized zeolitic materials exhibiting different properties, as well as zeolite/carbon and zeolite/vermiculite composites, to analyse their potential in removing aqueous BTEX. Various parameters and experimental conditions, including the type of volatile organic compounds (VOCs), initial concentration, BTEX coexistence, and increased solution salinity, were studied to verify the applicability of the derived materials. The adsorption capacity of the materials and their governing removal mechanisms were additionally elucidated. The primary removal mechanism involved partitioning on unburned carbon residues, which was observed in zeolite/carbon composites showing the highest BTEX removal efficiency. NaA-zeolite/carbon composite was the most effective in removal of BTEX, with the removal capacity of 15.36 mg/g towards p-xylene. Moreover, the increased salinity of the BTEX solution affects adsorption performance for polar adsorbates, irrespectively of the applied zeolite/carbon composite. Fly-ash (FA) and high-carbon fly-ash (HCFA) were successfully valorised into products with better textural features. These products may effectively tackle organic water pollution caused by VOCs under near-real-life conditions. [Display omitted] • Zeolitic materials, including zeolite/carbon composites, were obtained from HCFA. • Zeolite/carbon composites exhibited the highest efficiency of BTEX removal. • Unburned carbon residues resulted in partitioning which led to the highest BTEX removal. • The highest adsorption (15.36 mg/g for p-xylene) was observed for Na-A ZCC. [ABSTRACT FROM AUTHOR]

This study investigated the discoloration of real textile effluents using raw pyritic waste (RPW) as a Fenton-like process catalyst, as well as the influence of particle size and pre-treatment with distilled water only. The RPW was collected from a waste pile, following the ABNT NBR 10007:2004 standard, and ground to obtain particles with an average diameter of 0.75 and 1.5 mm. RPW and Washed Pyritic Waste (WPW) samples were characterized by XRF, FTIR and XRD. The operational conditions were assessed from an experimental design, varying the catalyst concentrations, H 2 O 2 and the reaction time. XRD results showed the majority presence of FeS 2 in the samples and the pre-treatment removed impurities, such as quartz and soluble compounds, from the catalyst surface. The experimental design determined that the 0.75 mm size was more efficient in removing colour from the effluent. The optimal condition was defined as 2 g/L of catalyst, 2 g/L of H 2 O 2 and 2 h. The effluent colour degradation capacity was greater than 90% for RPW and WPW samples. However, WPW released less iron into the resulting solution (10.51 mg/L). The catalyst proved to be stable for sequential use and after five cycles, the discoloration rate was greater than 80%. Root growth was verified for the Allium cepa test using the post-treatment and neutralized effluent. The results indicate a potential use of pyritic wastes from coal mining as catalysts for the Fenton process for real textile effluents discoloration, adding environmentally friendly value to a material considered an environmental liability. [Display omitted] • Brazilian pyritic waste used as catalyst in the real textile effluents discoloration. • Effluent discoloration using d p = 0.75 mm was 25.8% higher than for d p = 1.5 mm. • WPW had 91% of effluent discoloration, with the lowest Fe release (10.51 mg/L). • Pretreatment with distilled water removed impurities from the catalyst surface. • After five cycles, the discolouration rate is still higher than 80%. [ABSTRACT FROM AUTHOR]

High bauxite residue content inorganic polymer paving blocks have the potential not only to provide a solution to the ongoing waste management issues faced by the alumina sector, but to simultaneously provide low environmental impact building materials to the construction sector. In order to realise the potential of this emerging technology, it is important to understand where the hotspots of environmental impact are likely to occur, and identify routes to reduce this impact, at an early stage of development. In this study we use anticipatory Life Cycle Assessment (LCA) to identify hotspots of environmental impact in the production of paving blocks made from inorganic polymers derived from bauxite residue. This technology has only been demonstrated at laboratory scale; however, production was modelled at industrial scale. The bauxite residue is fired in a rotary kiln in the presence of a carbon and silica source, in order to create a reactive precursor. When mixed with an alkali the precursor forms a solid block. Our results identify the firing process as the major hotspot of environmental impact, primarily due to the combustion of fossil fuels in the rotary kiln. Steps to reduce the impact of the firing step or to reduce the amount of fired precursor used in the final paving block are suggested as routes for future impact reduction. Optimisation of the environmental aspects of these building materials at an early stage in their development could lead to a promising future for high-volume bauxite residue valorisation at low environmental cost. [ABSTRACT FROM AUTHOR]

Biphasic apatite-carbon biochar-type materials were prepared from pyrolysed cod fish bones and were assessed for the adsorption of persistent organic pollutants (pharmaceuticals diclofenac and fluoxetine), and heavy metals (Pb(II)). The materials, prepared with a simple pyrolysis process at different temperatures (200–1000 °C), were characterised with XRD, FTIR, Raman and SEM. Results showed that the pyrolysis temperature had a significant effect on the features/composition of the materials: up to 800 °C, carbonate apatite Ca 10 (PO 4 ) 6 (CO 3 ) was the main component, while for higher temperatures oxyapatite Ca 10 (PO 4 ) 6 O was the dominant phase. Graphitic carbon was also detected. The mixed apatite-carbon products (bone char) exhibited high adsorption efficiency. Graphite carbon was the main adsorber for the pharmaceuticals, the best performing material being that pyrolysed at 1000 °C. X m values of 43.29 and 55.87 mg/g were observed (Langmuir fitting), while K F values of 5.40 and 12.53 (mg/g)(L/mg) n F were obtained with the Freundhlich model (diclofenac and fluoxetine respectively). This is the first time that a biochar-like material has been used for fluoxetine adsorption. For Pb (II), the powder pyrolysed at 600 °C was the most effective, with the apatite playing a key role (X m = 714.24 mg/g). This work shows that a by-product of the fish industry could be converted into efficient materials for environmental remediation; according to the pyrolysis conditions, powders effective in the removal of either organics or heavy metals can be obtained. Moreover, with pyrolysis at intermediate temperatures, materials capable of adsorbing both kinds of pollutants can be produced, even if less efficient. [ABSTRACT FROM AUTHOR]

Continuing population growth and increasing consumption are driving global food demand, with agricultural activity expanding to keep pace. The modern agricultural system is wasteful, with Europe generating some 700 million tonnes of agrifood (agricultural and food) waste each year. The Agricultural Centre for Sustainable Energy Systems (ACSES) at Harper Adams University is involved in a major research and innovation project (AgroCycle) on the application of the ‘circular economy’ across the agri-food sector. In the context of the agrifood chain, the ‘circular economy’ aims to reduce waste while also making best use of the ‘wastes’ produced by using economically viable processes and procedures to increase their value . Led by University College Dublin, AgroCycle is a Horizon 2020 collaborative project with 26 partners. AgroCycle will address such opportunities directly by implementation of the ‘circular economy’ across the agri-food sector. The authors will present (a) a summary of the AgroCycle project and (b) the role played by Harper Adams in the project in evaluating the potential for small-scale anaerobic digestion (AD) technology that can be applied on farm to provide local heat, energy and nutrient recovery from mixed agricultural wastes. [ABSTRACT FROM AUTHOR]

Continuing population growth and increasing consumption are driving global food demand, with agricultural activity expanding to keep pace. The modern agricultural system is wasteful, with Europe generating some 700 million tonnes of agrifood (agricultural and food) waste each year. The Agricultural Centre for Sustainable Energy Systems (ACSES) at Harper Adams University is involved in a major research and innovation project (AgroCycle) on the application of the ‘circular economy’ across the agri-food sector. In the context of the agrifood chain, the ‘circular economy’ aims to reduce waste while also making best use of the ‘wastes’ produced by using economically viable processes and procedures to increase their value . Led by University College Dublin, AgroCycle is a Horizon 2020 collaborative project with 26 partners. AgroCycle will address such opportunities directly by implementation of the ‘circular economy’ across the agri-food sector. The authors will present (a) a summary of the AgroCycle project and (b) the role played by Harper Adams in the project in evaluating the potential for small-scale anaerobic digestion (AD) technology that can be applied on farm to provide local heat, energy and nutrient recovery from mixed agricultural wastes. [ABSTRACT FROM AUTHOR]

Wood industry continues to grow at a national and international scale producing considerable quantities of waste and related products such as branches, bark and sawdust. This considerable increase in waste pushed scientists to discover new methods for their valorisation, namely: energetic, for use as fuel, organic for the manufacture of composts and fertilizers and recycling materials for the manufacture of pulp, chipboard, etc. chemical treatment which we realized, during our work has resulted in the production of a pulp which contains cellulosic fibers. This treatment has several advantages as it allows using a minimum of chemical products and a simpler protocol. The present paper analyses the environmental aspects of resource recovery from chemically treated wood products (furniture, etc.). A life cycle assessment model of wood waste processing method in laboratory conditions is developed. Life cycle inventory is based on the data of laboratory experiments gathered in the laboratory of applied chemistry, Faculty of Science and Technology, University of Sidi Mohammed Ben Abdellah in Morocco. The analysed system boundary includes the collected wood waste after the first end of life, their transportation to the treatment plant, the chemical treatment and the final product. The result of assessment describes the environmental aspects of the analysed treatment method and the recommendations of further analysis proposed. [ABSTRACT FROM AUTHOR]

Climate change and ocean acidification are likely to have a profound effect on marine molluscs, which are of great ecological and economic importance. One process particularly sensitive to climate change is the formation of biominerals in mollusc shells. Fundamental research is broadening our understanding of the biomineralization process, as well as providing more informed predictions on the effects of climate change on marine molluscs. Such studies are important in their own right, but their value also extends to applied sciences. Biominerals, organic/inorganic hybrid materials with many remarkable physical and chemical properties, have been studied for decades, and the possibilities for future improved use of such materials for society are widely recognised. This article highlights the potential use of our understanding of the shell biomineralization process in novel bio-inspired and biomimetic applications. It also highlights the potential for the valorisation of shells produced as a by-product of the aquaculture industry. Studying shells and the formation of biominerals will inspire novel functional hybrid materials. It may also provide sustainable, ecologically- and economically-viable solutions to some of the problems created by current human resource exploitation. [ABSTRACT FROM AUTHOR]

The effect of two thermophilic amylase producing strains was evaluated using different mixtures of soy and bread wastes. Thermomyces sp. was found to be better inoculum than Geobacillus sp. for a soy and bread waste mixture (90:10 w/w respectively) producing a maximum enzyme activity of 39.9·10 3 U g −1 dry substrate. Three strategies (a, b, c) were evaluated for solid-state fermentation (SSF) operation in sequential batches. Fermented solids from each batch were used to inoculate the following batch: (a) solids at the moment of maximum biological activity; (b) final solids (end of the process, maximum amylase production); (c) final solids after enzymatic extraction. The evaluated strategies led to an increase in amylase production of 50, 500 and 98% for each strategy, respectively. This indicates the suitability of fermented solids to act as inoculum and the enhancement of amylase production compared to traditional batches. As one of the main challenges of SSF is the maintenance of a productive process along time, these results confirm SSF as an excellent option to produce amylases from organic wastes. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction (HTL) is identified as a promising thermochemical technique to recover biofuels and bioenergy from waste biomass containing low energy and high moisture content. The wastewater generated during the HTL process (HTWW) are rich in nutrients and organics. The release of the nutrients and organics enriched HTWW would not only contaminate the water bodies but also lead to the loss of valued bioenergy sources, especially in the present time of the energy crisis. Thus, biotechnological as well as physicochemical treatment of HTWW for simultaneous extraction of valuable resources along with reduction in polluting substances has gained significant attention in recent times. Therefore, the treatment of wastewater generated during the HTL of biomass for reduced environmental emission and possible bioenergy recovery is highlighted in this paper. Various technologies for treatment and valorisation of HTWW are reviewed, including anaerobic digestion, microbial fuel cells (MFC), microbial electrolysis cell (MEC), and supercritical water gasification (SCWG). This review paper illustrates that the characteristics of biomass play a pivotal role in the selection process of appropriate technology for the treatment of HTWW. Several HTWW treatment technologies are weighed in terms of their benefits and drawbacks and are thoroughly examined. The integration of these technologies is also discussed. Overall, this study suggests that integrating different methods, techno-economic analysis, and nutrient recovery approaches would be advantageous to researchers in finding way for maximising HTWW valorisation along with reduced environmental pollution. [Display omitted] • The wastewater from hydrothermal liquefaction has high amount of carbon and nutrient. • The review discusses various valorisation techniques of the wastewater. • Integrating various valorisation technologies are more encouraging. • Both the bioenergy and nutrient recovery should be targeted for an economical process. [ABSTRACT FROM AUTHOR]

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Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Fruit pomace of six different berries was extracted with scCO2 and hexane. • Green extractions to obtain added value products from food industry waste. • Fatty acids were extracted for the cosmetic industry. • Selectivity towards fatty acids was higher with scCO2. • The extraction yield was higher with hexane. One of the empowering actions for the circular economy is deriving value from waste. In this context, recycling waste agro-food streams to make more sustainable chemical products through greener technologies promises to move away from the linear development model based on continuous growth and increasing resource throughput. We describe here the use of supercritical fluid extraction with carbon dioxide to extract fatty acids from waste pomace deriving from the preserves industry along with a comparison using hexane as solvent. The fatty acids extracted from the seeds and peels of raspberry, blueberry, wild strawberry, pomegranate, blackberry and blackcurrant using supercritical CO 2 as a greener solvent were purer and richer in essential fatty acids than the hexane ones. The wild strawberry pomace extraction with supercritical CO 2 is a representative example: selectivity towards fatty acids was 26 wt% (vs. 1.4 % with hexane) and the extracts contained, 145.8 mg mL−1 polyunsaturated, 64.0 mg mL−1 monounsaturated and 46.8 mg mL−1 saturated fatty acids (vs. 14.3 mg mL−1 total fatty acids with hexane). [ABSTRACT FROM AUTHOR]

• Waste hops leaves and jimsonweed were extracted with scCO 2 and ethanol. • The yield of extracts with scCO 2 is lower than with ethanol. • The selectivity towards volatiles is higher with scCO 2. • The extracts are antimicrobial as tested towards E. coli. • scCO 2 extracts are more active as antibacterials compared to the ethanol ones The suitability of supercritical carbon dioxide (scCO 2) to extract cosmetic-friendly preservatives from low value weeds and agro-waste was investigated. The essential oils extracted from Humulus Lupulus and Datura Stramonium (leaves and flowers) were analysed in search for potential antibacterial compounds. Their antibacterial activity was evaluated against Escherichia coli in view of using the extracts as preservatives in cosmetic formulations. The composition and antibacterial activity of the scCO 2 extracts were compared to the ones obtained by Soxhlet extraction with ethanol. The two methods resulted very different in terms of yields, selectivity, composition, and antibacterial properties of the extracts. In general, scCO 2 was better for the recovery of preservative compounds since it led to the selective extraction of volatile oils composed mainly by terpenes, terpenoids, fatty acids, and bitter acids. [ABSTRACT FROM AUTHOR]