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This research introduces a low‐temperature catalytic‐assisted pyrolysis method for recycling waste thermosetting epoxy resins, transforming them into an efficient fire‐retardant additive for new epoxy resin formulations. In this study, we demonstrate that boric acid (BA) can significantly reduce the temperature required for epoxy resin (EP) pyrolysis, resulting in degradation products containing boron atoms that can act as a fire‐retardant additive. The impact of 5%–20% content of recycled EP (R‐EP) on the curing process, thermal stability, fire retardancy, and mechanical properties of the new EP was comprehensively investigated. The TGA results show that adding BA to epoxy resin at a 1:4 BA:EP ratio significantly reduces pyrolysis temperature. Neat EP degrades in two stages in 341°C and 557°C, while EP with BA degrades in three stages, starting below 120°C and peaking around 142°C. The results demonstrated an outstanding effect of incorporating 20% R‐EP on the char formation and fire retardancy of the new EP, surpassing the performance of 20% triphenyl phosphate (TPP), a commercially available fire retardant. The storage modulus for neat EP is 1510 MPa, increasing to 2280 MPa with EP/R‐EP 20%, indicating enhanced rigidity. Addition of R‐EP raised glass transition temperature (Tg) of the epoxy resin up to 38°C, indicating highly cross‐linked structures compared to TPP‐modified EP, which shows lower Tg values. [ABSTRACT FROM AUTHOR]

This study examines the domestic solid waste management system in the LATAM region, using the city of Guayaquil in Ecuador as a case study. Through the life cycle assessment (LCA) methodology, the study compares domestic and external recycling processes, evaluating their effects on global warming potential, fossil resource scarcity, and terrestrial ecotoxicity. The results reveal that increasing recycling rates significantly reduces environmental impacts, with domestic recycling offering slightly higher environmental benefits than external options. A demographic analysis using machine learning techniques identifies distinct patterns of waste generation across different population clusters, highlighting the need for tailored waste management strategies. The study also emphasizes the importance of accurate local data and the integration of recycling initiatives with market realities, particularly in the light of policies mandating recycled content in products like PET bottles. A sensitivity analysis of the waste recovery indicator (WRI) demonstrates the potential for substantial environmental and economic benefits with higher recycling rates. The findings suggest that, to advance towards a circular economy, Latin American cities like Guayaquil must enhance their recycling infrastructure, refine waste management policies, and focus on demographic-specific strategies. This research contributes to the broader understanding of sustainable waste management in developing regions, offering insights for future policy and infrastructure development. [ABSTRACT FROM AUTHOR]

Textile waste is a significant environmental problem that contributes to landfills and pollution that causes greenhouse gas emissions. Recycling and reusing textiles and developing a product from waste is feasible. Moreover, it can bring new opportunities in the recycling industry and contribute to the circular economy. However, choosing a material to produce a composite and finding out all its properties is a big challenge that needs to be explored more. This research is based on the characterization of a natural fiber composite from textile waste for domestic as well as industrial applications. It involves the production of composite material from textile waste, which has suitable mechanical strength and impact properties for use in the construction, automotive and ballistic industries. Three recycled non-woven wastes -- cotton, polyester and cotton/polyester blend -- are used. A roller speed of 200 rpm is chosen to produce carded mesh. The shredded textiles are then mixed with epoxy resin. The pressing technique with the help of compression moulding is used to produce composite samples. Mechanical tests were carried out to evaluate the young's modulus, tensile strength, flexural strength, impact strength and breaking elongation of the composites. It was found that with an increase in the volume percentage of fibers, the storage modulus of the prepared composites shows a higher value. Young's modulus, elongation at break, flexural strength and impact toughness increase with volume fraction up to 40 percent, but then the properties start to decrease again when mixing is done above 40 percent to 50 percent. The novelty lies in utilizing pre and post-consumer textile waste, including discarded personal protective equipment (PPE) and other textile wastes from the COVID-19 pandemic, as reinforcing fibers which contributes to textile waste recycling and also providing a better alternative to existing materials like pine wood, maple, oak and wood plastic composite for possible use in domestic items as well as construction and automotive industry at a lower cost. [ABSTRACT FROM AUTHOR]

Choconta is the municipality in Colombia with the greatest prevalence of potato planting, representing 70.90% of the total territory. However, this crop has been affected by the presence of pests, diseases, and chemical contaminants from pesticides and chemical fertilizers that deteriorate the soil and, therefore, the quality of the final product. Compost (organic waste with specific characteristics and made from waste generated in Choconta) was studied as a sustainable production strategy to increase soil quality and thereby the quality of the local potato crop. For this purpose, a 3 × 2 experiment design was implemented with three treatments (0%, 25%, and 50% compost) and two variables (young potato and mature potato) in duplicate for 4 months. In this experiment, the use of compost led to an improved final product, which went from a floury texture to a dense and creamy texture. The use of compost also reduced the levels of heavy metals, such as lead, with a higher removal in treatment 3 (50% composting). The estimated direct cost of the composting process was USD 280.85, slightly lower than that of the application of fertilizers at USD 294.48. The use of fertilizers has a higher environmental impact due to the use of chemical products that have environmental and health implications. Using compost did not influence tuber harvest time but had a positive impact on tuber texture quality and on soil resources through the reduction in heavy metals, especially lead (16.40–18.03 ppm for treatment 1, 17.96–18.49 ppm for treatment 2, and 15.67–17.88 ppm for treatment 3). Using compost could be environmentally and economically beneficial for local farmers, and it promotes the circular economy and sustainable communities. [ABSTRACT FROM AUTHOR]

Abstract Phosphorus-modified biochar has been proven to enhance the precipitation and complexation of heavy metal ions from wastewater. However, the current modification methods require large amounts of exogenous P and have high energy consumption. Hence, this study proposes and analyzes a strategy integrating biochar production, phosphorus wastewater treatment, dephosphorization waste recovery, and heavy metal removal. “BC-Ca-P” was derived from Ca-modified biochar after phosphorus wastewater treatment. The adsorption of Pb(II) by BC-Ca-P followed the Langmuir isotherm and pseudo–second–order kinetic models. The maximum adsorption capability of 361.20 mg·g−1 at pH 5.0 for 2 h was markedly greater than that of external phosphorous-modified biochar. The adsorption mechanisms were dominated by chemical precipitation and complexation. Furthermore, density functional theory calculations indicated that oxygen-containing functional groups (P-O and C-O) contributed the most to the efficient adsorption of Pb(II) onto BC-Ca-P. To explore its practical feasibility, the adsorption performance of BC-Ca-P recovered from an actual environment was evaluated. The continuous-flow adsorption behavior was investigated and well-fitted utilizing the Thomas and Yoon–Nelson models. There was a negligible P leakage risk of BC-Ca-P during heavy metal treatment. This study describes a novel and sustainable method to utilize dephosphorization waste for heavy metal removal. Graphical Abstract

In this study, we report a base‐catalyzed transesterification reaction of glycerol, a waste product of the biodiesel industry, with various dialkyl carbonates, which act both as reactants and solvents, to convert glycerol carbonate into an industrially useful molecular building block. The catalyst, being used for the first time, is also a waste product from industry, present in bauxite residues and in the Portland cement, simply known as tricalcium aluminate. Despite being well‐known and readily available, this solid is only extremely poorly researched catalyst, nevertheless, using dimethyl and diethyl carbonate, glycerol conversion rates >80% and glycerol carbonate yields >60% could be achieved in just 1 h (under air atmosphere and reflux). In a comparison of the performance with other catalysts commonly researched today, as well as with other components of red mud and cements, the results showed that tricalcium aluminate is excellent, cheap, and largely environmentally friendly material for this purpose. Reusability studies of the catalysts have also shown that they provide high conversion and product yields even after repeated use, although different material characterization techniques showed intense glycerol‐catalyst surface interaction and intermediate product formation, the deactivating side effects of which could be avoided by catalyst regeneration steps. [ABSTRACT FROM AUTHOR]

Phosphorus-modified biochar has been proven to enhance the precipitation and complexation of heavy metal ions from wastewater. However, the current modification methods require large amounts of exogenous P and have high energy consumption. Hence, this study proposes and analyzes a strategy integrating biochar production, phosphorus wastewater treatment, dephosphorization waste recovery, and heavy metal removal. "BC-Ca-P" was derived from Ca-modified biochar after phosphorus wastewater treatment. The adsorption of Pb(II) by BC-Ca-P followed the Langmuir isotherm and pseudo–second–order kinetic models. The maximum adsorption capability of 361.20 mg·g−1 at pH 5.0 for 2 h was markedly greater than that of external phosphorous-modified biochar. The adsorption mechanisms were dominated by chemical precipitation and complexation. Furthermore, density functional theory calculations indicated that oxygen-containing functional groups (P-O and C-O) contributed the most to the efficient adsorption of Pb(II) onto BC-Ca-P. To explore its practical feasibility, the adsorption performance of BC-Ca-P recovered from an actual environment was evaluated. The continuous-flow adsorption behavior was investigated and well-fitted utilizing the Thomas and Yoon–Nelson models. There was a negligible P leakage risk of BC-Ca-P during heavy metal treatment. This study describes a novel and sustainable method to utilize dephosphorization waste for heavy metal removal. Article Highlights: Dephosphorization biochar waste was used to sustainably remove heavy metals from wastewater. Field-recovered dephosphorization biochar waste displayed high Pb adsorption capacity. Dephosphorization biochar for heavy metal removal is an eco–friendly waste–reduction and resource–utilization method. [ABSTRACT FROM AUTHOR]

This study investigates the performance of different poly(lactic acid) (PLA) composites incorporating agri-food waste additives and commercial lignin, comparing their properties with those of virgin PLA. The following composites were prepared using a single-screw extruder: PLA with 20% rice husk, PLA with 20% wheat straw and PLA with 20% olive pit. Additionally, PLA was blended with commercial lignin at the maximum feasible proportion using the same methodology. The resulting composites were injection-molded into specimens for analysis of their mechanical, thermal and morphological behavior. The primary objectives were to assess the dispersion of the additives within the PLA matrix and to evaluate the mechanical properties of the composites. The results indicate that the addition of high percentages of agricultural residues does not significantly compromise the mechanical properties of the composites. Notably, in the case of the PLA with 20% rice husk composite, the elastic modulus surpassed that of virgin PLA, despite the evident heterogeneity in filler particle sizes. It was feasible to incorporate a higher percentage of agricultural residues compared to commercial lignin, attributed to the larger volume occupied by the latter. [ABSTRACT FROM AUTHOR]

In order to obtain solutions to the coal mining region demand in southern Brazil for high-performance and low-cost technosols within a concept of mineral circularity and sustainable development of the coal sector, this study aims to evaluate the functional feasibility of the combined use of a residual fraction of coal tailing, waste from the rice and poultry agro-industry, as well as the cellulose industry, as raw materials for technosol development. Characterizations (XRF, LOI, ICP-OES, pH, XRD, and sulfur forms) were performed to adjust the waste proportions used in the constructed soil, as defined based on the clay content of the coal tailing, the organic carbon content of the poultry litter, and technical recommendations for the use of synthetic gypsum in agricultural soils. Based on the characterizations of the residues, a greenhouse experiment was designed, consisting of four technosol formulations (T1–T4). Initially, an ecotoxicity test was conducted with the treatments in contact with Allium cepa L. (onion) to determine the degree of technosol toxicity. Field tests were then carried out, which were replicated three times in a completely randomized block design, with the germination and growth of Lactuca sativa L. (crisp lettuce) as a bioindicator. The fertility of the treatments was analyzed eight weeks after the establishment of the experiment and compared to standard values for agricultural soils. The characterization performed with the individual wastes demonstrated the potential for application in technosols according to current regulations. The ecotoxicity tests showed that the soil was not toxic to the plant in any of the treatments studied. The field experiment demonstrated no difference in germination between the treatments. However, the development of lettuce seedlings occurred only in technosol formulations T2 and T3, highlighting the potential of the studied residues for the construction of technosols. [ABSTRACT FROM AUTHOR]

Originating from furniture scraps, packaging, urban tree pruning, and construction waste, urban wood waste generates surprisingly large annual volumes. Due to its abundance and interesting physical–chemical characteristics for its use, it can be an excellent alternative for generating renewable energy for heat and electricity. In this context, urban wood waste's physical, chemical, and energetic properties were investigated, proposing alternative environmental routes for its introduction into the urban and industrial electricity sectors. Waste collected in Piracicaba (Brazil) was evaluated for physical and chemical composition, such as moisture, bulk density, particle size distribution, mineral contaminants, immediate chemical composition, chemical composition, and calorific value analysis. The waste studied presented potential characteristics for bioenergy generation, with ash and contaminant contents (such as metallic materials and sand) within the quality thresholds established by the energy sector. Among the waste materials analyzed, plywood, chipboard, wood, and OSB stood out for their high energy density (averaging 2.97 GJ/m3) and low ash content (averaging 1.13%). In contrast, MDF and hardboard exhibited lower calorific values and energy densities due to the wood cooking step in their manufacturing process, which could result in the loss of extractives and volatile materials. When categorizing the residues based on their characteristics, three distinct groups emerged, each associated with MDF, hardboard, or a combination of chipboard, OSB, wood, and plywood. This study's findings support the creation of public policies aimed at valorizing and reusing urban wood waste, contributing to solid waste management in cities of different countries while sustainably generating energy. [ABSTRACT FROM AUTHOR]

It is widely recognized that foods, biodiversity, and human health are strongly interconnected, and many efforts have been made to understand the nutraceutical value of diet. In particular, diet can affect the progression of intestinal diseases, including inflammatory bowel disease (IBD) and intestinal cancer. In this context, we studied the anti-inflammatory and antioxidant activities of extracts obtained from a local endangered variety of Phaseolus vulgaris L. (Fagiola di Venanzio, FV). Using in vitro intestinal cell models, we evaluated the activity of three different extracts: soaking water, cooking water, and the bioaccessible fraction obtained after mimicking the traditional cooking procedure and gastrointestinal digestion. We demonstrated that FV extracts reduce inflammation and oxidative stress prompted by interleukin 1β through the inhibition of cyclooxygenase 2 expression and prostaglandin E2 production and through the reduction in reactive oxygen species production and NOX1 levels. The reported data outline the importance of diet in the prevention of human inflammatory diseases. Moreover, they strongly support the necessity to safeguard local biodiversity as a source of bioactive compounds. [ABSTRACT FROM AUTHOR]

Green roofs are nature-based solutions with multiple benefits for the urban environment, but they have specific polymeric components in their structure that cause a carbon footprint. This scoping review highlights the technological advance in reusing or recycling alternative materials in green roof structures worldwide, making them a part of the circular economy (CE), and the search strategies to promote them to find whether there is a relation between them. The data were collected using the Web of Science from 2012 to 2022; we also used the Bibliometrix package to analyse research development by country and the development of the topic by author's keywords. We selected 68 open-access articles from twenty-four countries and reviewed the grey literature from the top five productive countries on this topic. Our findings show that CE strategies are performed nationally, while the green roof promotion ones are concentrated at the city level. The theme co-occurrence analysis showed that the substrate is the primary layer used with alternative materials, and the three materials most applied for it are rubber, biochar, and hydrogel. It was found that the primary purpose of optimising green roofs with alternative materials is to increase the ecosystem services they provide and indirectly function within the circular economy; still, there is a gap in estimating the environmental impact of doing this as a potential CE activity. [ABSTRACT FROM AUTHOR]

Fruit and vegetable industries face a major environmental challenge with food loss and waste. Broccoli stems, comprising 38% of the plant's total weight, are usually discarded by the industry producing fourth-range and ready-to-use products, despite being rich in antioxidants, vitamins, fiber, carotenoids, phenolic compounds, and glucosinolates. Addressing the challenge of reducing waste in this sector includes the production of stable and nutrient-concentrated powders, which can be consumed directly or used as ingredients in functional food formulation. This study investigated fermentation with lactic acid bacteria (Limosilactobacillus reuteri, Lactiplantibacillus plantarum, and Lactobacillus salivarius) as a pretreatment for enhancing antioxidant and probiotic potential in broccoli stem powders. Results showed maximum counts 24 h after inoculation, and no effect of the previous disruption intensity on microbial growth was observed. Fermenting broccoli stems for 24 h with the three microbial strains led to a significant increase in total phenols and flavonoids but to a general reduction in the samples' capacity to scavenge DPPH and ABTS free radicals. Overall, ground broccoli stems exhibited the most favorable antioxidant properties following the 24 h fermentation step. The subsequent freeze-drying and final grinding had minimal impact on the microbial population but significantly enhanced the extractability of the antioxidant compounds. This study offers a valuable reference for researchers and stakeholders exploring the development of new products and innovations from vegetable waste.

Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate. A new acid leaching–flotation process for fluorite is proposed in this work. This innovative process raised the fluorite's grade to 97.26wt% while producing nanoscale calcium carbonate from its leachate, which contained plenty of calcium ions. On the production of nanoscale calcium carbonate, the impacts of concentration, temperature, and titration rate were examined. By modifying the process conditions and utilizing crystal conditioning agents, calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511 µm were produced. The influence of the impurity ions Mn2+, Mg2+, and Fe3+ was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution. The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources, thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles. [ABSTRACT FROM AUTHOR]

Several studies have explored the potential of waste marble powder (WMP) and lime (LM) as solutions for issues associated with clayey soils. While WMP enhances mechanical properties and addresses environmental concerns, LM effectively improves soil characteristics. This research investigates the efficacy of LM and WMP, both individually and in combination, in addressing challenges specific to clayey soils in Bouzaroura El Bouni, Algeria. These soils typically exhibit low load-bearing capacity, poor permeability, and erosion susceptibility. LM demonstrates promise in enhancing soil properties, while WMP not only addresses environmental concerns but also enhances mechanical characteristics, providing a dual benefit. The study utilizes a three-variable experiment employing Response Surface Methodology (RSM) Box-Behnken Design, with variations in clay content (88%-100%), LM treatment (1.5%-9%), and WMP inclusion (1.5%-9%). Statistical analysis, including ANOVA, reveals significant patterns with p-values <5%. Functional relationships between input variables (clay, LM, and WMP) and output variables (cohesion, friction angle, and unconfined compressive strength) are expressed through high determination coefficients (R2 = 99.84%, 77.83%, and 96.78%, respectively). Numerical optimization identifies optimal mixtures with desirability close to one (0.899-0.908), indicating successful achievement of the objective with 88% clay content, 3% LM, and 6% WMP. This study provides valuable insights into optimizing clay soil behavior for environmental sustainability and engineering applications, emphasizing the potential of LM and WMP as strategic additives. [ABSTRACT FROM AUTHOR]

The article deals with the problem of waste management in Algeria. It aims to analyze the various policies undertaken by the government in order to be able to respond to the principles of sustainable development and the circular economy from the perspective of sustainable and integrated waste management. The analyses carried out show that the first waste management strategies in Algeria were highly reactive and constituted a response to the exponential increase in waste. It is only since the year 2016 that the National Strategy for Integrated Waste Management has constituted an attempt at regulating this sector via a circular approach of profitability and sustainability. [ABSTRACT FROM AUTHOR]

To address the growing global water demand, it is imperative to implement advanced treatment systems and sustainable alternatives for managing the large amount of waste generated during the water purification process, known as water treatment sludge (WTS). Worldwide, researchers and companies are exploring alternatives and methods for the valorization of WTS as a raw material in other processes. It is urgent that all productive sectors, which contribute significantly to greenhouse gas emissions, adopt this management principle to ensure more sustainable production, contributing to the global goal of climate neutrality. Notably, in civil construction, incorporating WTS as a supplementary cementitious material (SCM) shows great promise, considering that the industrial waste currently used for this purpose is increasingly restricted. The use of WTS as a raw material in the cement industry not only contributes to the reduction of the carbon footprint, but also reduces the high waste load still disposed of in landfills. The emerging applications for WTP sludge are reviewed, with emphasis on its valorization in the civil construction as an SCM. The main characteristics of this waste and their impacts on the environment are also addressed. [ABSTRACT FROM AUTHOR]

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Fruit and vegetable industries face a major environmental challenge with food loss and waste. Broccoli stems, comprising 38% of the plant's total weight, are usually discarded by the industry producing fourth-range and ready-to-use products, despite being rich in antioxidants, vitamins, fiber, carotenoids, phenolic compounds, and glucosinolates. Addressing the challenge of reducing waste in this sector includes the production of stable and nutrient-concentrated powders, which can be consumed directly or used as ingredients in functional food formulation. This study investigated fermentation with lactic acid bacteria (Limosilactobacillus reuteri , Lactiplantibacillus plantarum , and Lactobacillus salivarius) as a pretreatment for enhancing antioxidant and probiotic potential in broccoli stem powders. Results showed maximum counts 24 h after inoculation, and no effect of the previous disruption intensity on microbial growth was observed. Fermenting broccoli stems for 24 h with the three microbial strains led to a significant increase in total phenols and flavonoids but to a general reduction in the samples' capacity to scavenge DPPH and ABTS free radicals. Overall, ground broccoli stems exhibited the most favorable antioxidant properties following the 24 h fermentation step. The subsequent freeze-drying and final grinding had minimal impact on the microbial population but significantly enhanced the extractability of the antioxidant compounds. This study offers a valuable reference for researchers and stakeholders exploring the development of new products and innovations from vegetable waste. [ABSTRACT FROM AUTHOR]

This study was performed in order to identify the role and work mechanism of the 33 junkshops in the recovery of valuable recyclable materials for further processing by the next level hierarchy of recycling chain actors in Iloilo City, Philippines. Results revealed that more than 65% of the junkshops operate at 7 to 8 hours per day, hire 1 to 4 male workers, operate at an area of 50 to 1000 m2 with structures made of light materials, and with a capital outlay of

Banana fruit is a highly consumed and widely cultivated world food crop that generates plenty of waste globally. In this work, the phytochemical, nutritional, scavenging and therapeutic potentials of banana peel (BP) extracts were compared before and after fermentation. Halophilic fungi (Alternaria alternata, Pleosporaceae spp., Fusarium culmorum) were used in fermentation media designated as fermented banana peel FBP1, FBP2, and FBP3, respectively. Phytochemical coumarins, terpenoids, tannins, saponins, quinones, flavonoids, alkaloids, carbohydrates, proteins and steroids were found in all extracts while anthraquinone was identified in BP extracts only. Fermented extracts showed less quantity of Carbohydrate, compared to BP (477.1 ± 28.93 mg/g). Fermentation influenced the protein concentration as FBP1 showed a maximum protein of 56.9 ± 8.91 mg/g. Decreased quantities of Total Phenolic Contents (TPC), Total Flavonoid contents (TFC), and Vitamin C were noted in fermented products. The BP contained TPC (18 ± 2.59 mg GAE/g), TFC (20.5 ± 2.11 mg QE/g), carotenoid (1.03 ± 0.19 mg/g) and vitamin C (33.46 ± 2.63 mg/L). For BP, high antioxidant activity was observed, IC50 values of DPPH scavenging and FRAP assay were 2.01 ± 0.06 mg/mL and 12.81 ± 0.03 mg/mL, respectively. All the extracts were potentially active against the Salmonella typhi, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli BP extract showed high antibacterial activity than the fermented products. Among all the above, S. aureus showed high sensitivity to BP and FBP2 with 26.33 ± 2.49 and 26.33 ± 0.97 mm zone of inhibition and S. typhi was highly inhibited by BP and FBP1 with 26.26 ± 1.77 and 26.66 ± 2.63 mm. BP was highly active against K. pneumoniae and P. aeruginosa with 31.33 ± 1.74 and 32.33 ± 1.59 mm zone of inhibition and E. coli was sensitive to FBP2 with 25.7 ± 2.33 mm zone, respectively. The BP extract possessed potent antifungal activity against Mucor mucedo (84 %), Aspergillus niger (72 %) and Aspergillus flavus (83 %), which was higher than the fermented products. The antileishmanial assay was undertaken for all extracts against promastigotes of Leishmania major, BP showed good activity IC50 = 0.763 ± 0.01 mg/g. In the anti-inflammatory assays the BP showed lowest IC50 values by protein denaturing (0.612 ± 0.01), proteinase inhibitory (0.502 ± 0.01) and blood hemolysis assay (0.515 ± 0.01 mg/g). The minimum concentration indicated that BP was highly potent in response to antileishmanial and inflammation activity.

Extractive waste (EW), including tailings, is produced in large quantities during mining activities. In recent years, the linear economic model (“take-use-and-throw” approach) has been replaced by a circular approach, emphasizing the sustainable use and recovery of EW. The development of innovative protocols, such as Best Available Techniques (BATs), which aim at the technological and process improvement of more sustainable mining activities and at the production of renewable, highly performing green materials, has led to technological advancements, expertise in sustainability, and a reduced ecological footprint, potentially causing positive economic and social impacts and reducing environmental ones. Extractive waste and tailings, if suitably characterized, can be used to improve and make sustainable the works connected to the management of mining activities. The qualitative–quantitative characterization of EW is essential for subsequent reuse and for assessing the risk to human health and the extent of environmental impacts in the various matrices. The application areas vary according to the type of waste and mining tailings, the morphological characteristics of the deposits, and the geological, geomorphological, and logistic context of the area. Integrated protocols for sustainable EW exploitation and positive impacts on the economic, environmental, and technological/social level are analyzed. The present paper aims at providing an overview of challenges and potentialities connected to extractive waste (EW) management and potential exploitation to recover raw materials (RM), critical raw materials (CRM), and secondary raw materials (SRM).

Extractive waste (EW), including tailings, is produced in large quantities during mining activities. In recent years, the linear economic model ("take-use-and-throw" approach) has been replaced by a circular approach, emphasizing the sustainable use and recovery of EW. The development of innovative protocols, such as Best Available Techniques (BATs), which aim at the technological and process improvement of more sustainable mining activities and at the production of renewable, highly performing green materials, has led to technological advancements, expertise in sustainability, and a reduced ecological footprint, potentially causing positive economic and social impacts and reducing environmental ones. Extractive waste and tailings, if suitably characterized, can be used to improve and make sustainable the works connected to the management of mining activities. The qualitative–quantitative characterization of EW is essential for subsequent reuse and for assessing the risk to human health and the extent of environmental impacts in the various matrices. The application areas vary according to the type of waste and mining tailings, the morphological characteristics of the deposits, and the geological, geomorphological, and logistic context of the area. Integrated protocols for sustainable EW exploitation and positive impacts on the economic, environmental, and technological/social level are analyzed. The present paper aims at providing an overview of challenges and potentialities connected to extractive waste (EW) management and potential exploitation to recover raw materials (RM), critical raw materials (CRM), and secondary raw materials (SRM). [ABSTRACT FROM AUTHOR]

Recycled product certification (RPC) schemes may prove useful to ensure the desired quality and gain buyer confidence in purchasing products with recycled content (PwRC). RPCs are relatively new to the sector and have not been widely adopted. Hence, this study aims to investigate the implementation of RPC in construction projects using a multiple‐case study approach. The analysis reveals that a large proportion of respondents were unaware of these schemes. The study finds that while a majority favoured RPC application, there were significant variations in responses among stakeholder groups. Moreover, the study identifies six advantages and seven significant barriers associated with the use of RPC in the sector. This study recommends leveraging education and supportive regulation for the effective implementation of RPC. In particular, the policymakers who intend to embed RPC in procurement policies for purchasing PwRC can learn about the identified loopholes and strategies and address them accordingly. [ABSTRACT FROM AUTHOR]

Calcium carbonate (CaCO3) particles have attracted increasing attention as a promising material for drug delivery systems. In this study, coral remains were utilized as a raw material for a novel drug carrier. A series of pre-treatment and parameter experiments were conducted to synthesize sub-micron spherical CaCO3 particles. The CaCO3 particles exhibited uniform size distribution, with the minimum mean size being only 344 nm. The effects on the CaCO3 crystal phases and particle sizes were also discussed in this study. Drug loading experiments were also conducted to assess the feasibility of the CaCO3 drug carrier. We loaded TRITC-Dextran into CaCO3 particles for the simulation experiments. The loading capacity reached up to 9.6 wt.%, which was as high as common drug carriers such as liposomes. In this study, we aimed not only to tackle the local environmental issues caused by coral remains, but also to synthesize a suitable drug carrier for cancer therapy using the outstanding properties and low cost of CaCO3. [ABSTRACT FROM AUTHOR]

Meat industry is a major generator of organic waste in the food processing sector. On the technological flows of slaughterhouses, solid and liquid waste is generated, represented by certain parts of slaughtered animals, considered worthless for the operator of the slaughterhouse. Also, large amounts of wastewater are generated as a result of washing animal carcasses, processing organs, cleaning equipment and halls etc. European regulations for waste management seek to minimize the amount of waste that ends up in ecological landfills and emphasize the importance of recycling and recovery of resources. In this context, this paper reviews some of the most well-known methods and technologies for the treatment and recovery of waste and by-products resulting from technological flows from meat industry. [ABSTRACT FROM AUTHOR]

Introduction. The Municipality of Choconta is known for being the largest producer of papa in Colombia. However, these advantages have been overshadowed by the use of chemical fertilizers, crop diseases, waste accumulation and climate change, which aggravate soil quality and alterations in the physicochemical properties of the crop. Objective. Select the cleanest production strategy for soil resources for potato cultivation based on waste recovery. Materials and methods. A bibliographic review of cleaner production strategies for agricultural crops was carried out. The characterization and selection matrix of the most effective strategy for the recovery of waste and the reduction of contamination in the soil resource was carried out. Results. The characterization of cleaner production strategies was carried out for the improvement of soil resources and agricultural crops from the valorization of waste through composting as a cleaner production strategy. Conclusions. Potato cultivation is affected by environmental pollution generated by climate change, accumulation of heavy metals, chemical fertilizers, among others, which is why it is necessary to characterize cleaner production strategies for the use of organic waste in the improvement of the quality of the crop and the soil for agricultural activity in the region. [ABSTRACT FROM AUTHOR]

The production of construction and demolition waste (CDW) in urban areas is growing rapidly. While the storage and disposal of CDW waste is costly, its recovery can help to conserve natural resources. This study investigates the characteristics of recycled sand obtained from the processing of CDW waste and the possibility of its reuse for pedestrian pathways. Physico-chemical and mineralogical characteristics of the recycled sand were investigated for its reuse. The percentage of fine particles in sand (below 0.63 μm) is 2.8%. The grain size of sand fulfills the particle size requirement of French standards. The methylene blue value of sand is 0.05 g/100 g. The GTR classification of recycled sand is D2 which is insensitive to water and suitable for road applications. A mineralogical analysis of soil shows that quartz, albite and microcline are important minerals in recycled sand. XRF analysis shows that CaO and SiO2 are major oxides in the recycled sand. The characterization of sand was followed by a manufacturing of cylindrical specimens of sand to observe the compressive strength. Samples were compacted with dynamic compaction by applying the Proctor normal energy of 600 kN·m/m3. The compressive strength testing of specimens shows that non-stabilized sand samples have compressive strength around 0.1 MPa which is considerably lower for its reuse in pedestrian pathways and road applications. Due to the low bearing capacity of sand, recycled sand was stabilized with the addition of binders such as Rolac (hydraulic binder), ground-granulated blast furnace slag (GGBS) and ECOSOIL® (slag mixes) with different percentages of the binder ranging from 0 to 7% for the optimization of the binder and for economic efficiency. The compressive strength of sand samples increases with the increasing percentage of the binder. The increase in strength is more important with a higher percentage of binders (5%, 6% and 7%). At a 7% binder addition, specimens with Rolac, GGBS and ECOSOIL binders show the compressive strength of 1.2 MPa, 0.5 MPa and 0.5 MPa. At a 7% Rolac addition, specimens have a compressive strength higher than 1 MPa and meet the strength requirement for soil reuse in the foundation and subbase layers of roads with low traffic. The experimental work shows that recycled sand can replace conventional quarry sand for road applications and pathways with the addition of a local binder, which is an eco-friendly and economical practice. [ABSTRACT FROM AUTHOR]

The recovery of waste vegetable oil is a complex problem due to the variety of sources that generate it. The current collection systems do not manage to collect all the waste vegetable oil. The collection system must solve two main problems: identify the location of both the collection points and the collection centers and design routes that guarantee the optimization of resources. Therefore, the objective of this article was to develop a waste vegetable oil logistics collection system. The system integrates all sources of waste vegetable oil generation classified into three sectors: industrial, services, and residential, and it optimizes the collection routes. The developed system was compared with the current collection system that operates in Mexicali city. The developed system increases the collected waste vegetable oil by 1078%, reduces the fuel consumption per route by 37%, and improves the transportation capacity utilization by 93%. In addition, it decreases transportation costs by 73%. Water pollution is reduced by 78% and CO2e emissions per route by 14%. The waste vegetable oil collection logistics system can be implemented in any city since it adapts to its needs and characteristics. [ABSTRACT FROM AUTHOR]

Abstract The use of mango peel, an agro-industrial byproduct rich in bioactive compounds, was the subject of this study, seeking an innovative application in the manufacture of sliced bread. This process is proposed as a way to create a nutritious and healthy food, rich in dietary fiber and total polyphenols. Mango peel flour of the Kent variety was obtained by drying, grinding, and sieving. An experimental design through the Response Surface Methodology (RSM) with a central composite rotatable design, was used to evaluate the impact of mango peel flour (5% to15%) and ascorbic acid (20 to100 ppm) in the bread formulation. Technological, sensory evaluations, and determinations of polyphenols and dietary fiber were carried out, using standard methods. The results showed that mango peel flour and ascorbic acid influence the texture of the bread, with formulations of 10% mango peel flour and 60 ppm ascorbic acid obtaining the best sensory ratings in color, appearance, aroma, and texture. The mango peel flour increased the fiber up to 13.25 g/100 g and polyphenols up to 1.187 g AGE/g dry weight (DW) in the sliced bread. These findings suggest that the inclusion of mango peel flour improves the nutritional and sensory quality of bread, showing its potential as a functional ingredient in the food industry.

Several studies have explored the potential of waste marble powder (WMP) and lime (LM) as solutions for issues associated with clayey soils. While WMP enhances mechanical properties and addresses environmental concerns, LM effectively improves soil characteristics. This research investigates the efficacy of LM and WMP, both individually and in combination, in addressing challenges specific to clayey soils in Bouzaroura El Bouni, Algeria. These soils typically exhibit low load-bearing capacity, poor permeability, and erosion susceptibility. LM demonstrates promise in enhancing soil properties, while WMP not only addresses environmental concerns but also enhances mechanical characteristics, providing a dual benefit. The study utilizes a three-variable experiment employing Response Surface Methodology (RSM) Box-Behnken Design, with variations in clay content (88%–100%), LM treatment (1.5%–9%), and WMP inclusion (1.5%–9%). Statistical analysis, including ANOVA, reveals significant patterns with p-values

Choconta is the municipality in Colombia with the greatest prevalence of potato planting, representing 70.90% of the total territory. However, this crop has been affected by the presence of pests, diseases, and chemical contaminants from pesticides and chemical fertilizers that deteriorate the soil and, therefore, the quality of the final product. Compost (organic waste with specific characteristics and made from waste generated in Choconta) was studied as a sustainable production strategy to increase soil quality and thereby the quality of the local potato crop. For this purpose, a 3 × 2 experiment design was implemented with three treatments (0%, 25%, and 50% compost) and two variables (young potato and mature potato) in duplicate for 4 months. In this experiment, the use of compost led to an improved final product, which went from a floury texture to a dense and creamy texture. The use of compost also reduced the levels of heavy metals, such as lead, with a higher removal in treatment 3 (50% composting). The estimated direct cost of the composting process was USD 280.85, slightly lower than that of the application of fertilizers at USD 294.48. The use of fertilizers has a higher environmental impact due to the use of chemical products that have environmental and health implications. Using compost did not influence tuber harvest time but had a positive impact on tuber texture quality and on soil resources through the reduction in heavy metals, especially lead (16.40–18.03 ppm for treatment 1, 17.96–18.49 ppm for treatment 2, and 15.67–17.88 ppm for treatment 3). Using compost could be environmentally and economically beneficial for local farmers, and it promotes the circular economy and sustainable communities.

Green roofs are nature-based solutions with multiple benefits for the urban environment, but they have specific polymeric components in their structure that cause a carbon footprint. This scoping review highlights the technological advance in reusing or recycling alternative materials in green roof structures worldwide, making them a part of the circular economy (CE), and the search strategies to promote them to find whether there is a relation between them. The data were collected using the Web of Science from 2012 to 2022; we also used the Bibliometrix package to analyse research development by country and the development of the topic by author’s keywords. We selected 68 open-access articles from twenty-four countries and reviewed the grey literature from the top five productive countries on this topic. Our findings show that CE strategies are performed nationally, while the green roof promotion ones are concentrated at the city level. The theme co-occurrence analysis showed that the substrate is the primary layer used with alternative materials, and the three materials most applied for it are rubber, biochar, and hydrogel. It was found that the primary purpose of optimising green roofs with alternative materials is to increase the ecosystem services they provide and indirectly function within the circular economy; still, there is a gap in estimating the environmental impact of doing this as a potential CE activity.

In Argentina, after the economic, social, and institutional 2001 crisis, there was a substantial rise in the number of people informally collecting and selling recyclable waste. This activity had been ongoing for a long time, but the significant increase brought attention to an activity previously regarded as unlawful and illicit. From then on, even with discontinuities and drifts, a clear trend was consolidated towards the incorporation of informal collectors (colloquially called cartoneros/as) in public solid waste management systems, which implies, among other factors, a significant improvement in their working conditions. This article examines the establishment of the waste collection circuit over time and how its various regulations have impacted the work processes of cartoneros. It also explores the political and social organizations developed by the collectors, enabling them to negotiate and dispute the terms of this implementation. From our analysis, we suggest that a progression from poverty to recovery occurred, despite poverty remaining a fundamental aspect of the activity.

Finding eco-friendly products that are beneficial to the environment and serve as tools for sustainable development is a contemporary challenge. This work illustrates the recovery of bio-waste-based materials, which not only improve the hygrothermal properties of gypsum but also promote the paper and wood recycling processes in a circular economy approach. The samples were subjected to tests for density, water absorption, ultrasonic pulse velocity, flexural strength, compressive strength, and thermophysical property characterization. A statistical analysis of variance was used to study the impact of waste on the physico-mechanical behavior of gypsum, leading to the development of predictive models that can be used to predict and optimize the performance of bio-composites in various applications. The results revealed a reduction in mechanical strength with the addition of waste, but the samples still exhibit superior insulation properties, surpassing commonly used standard boards. By adding ouate and wood wastes to a mass of 20% in its natural state, the gypsum becomes lighter and acts as a better insulator with a reduced density, thermal conductivity, and ultrasound velocity of up to 50%, 57%, and 83%, respectively. These findings show the significant implication of reducing environmental impacts while contributing to the promotion of sustainable building practices, both in new construction projects and in building renovations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine changes in the organic nitrogen fraction in the liquid fraction of the digestate during laboratory tests of mono- and co-digestion. Three agricultural wastes were tested: distillery residue, cattle slurry and corn silage. In the mono-fermentation tests, the initial total nitrogen concentration depended on the feedstock used. As a result of the hydrolysis and ammonification of the organic matter contained in the feedstocks, there was an increase in ammonium nitrogen concentration after 28 days of fermentation. Analysis of organic nitrogen fractions showed that different organic nitrogen fractions predominated in each of the feedstocks. Four co-digestion tests were performed with 20% and 80% inoculum content and the combination of feedstocks used in the mono-fermentation. Proper evaluation of the transformation of nitrogen forms for the tests with 20 and 80% inoculum participation required the calculation of concentrations from the mass balance, taking into account the effect of changes taking place in the inoculum itself (control test). For these tests, the initial concentrations of nitrogen forms are similar to those found in the mono-fermentation tests. A greater increase in ammonium nitrogen concentrations was found for the test with 80% inoculum than in the test with 20% (for the same feedstock). An increase in the removal efficiency of the dissolved organic nitrogen fraction (DON), and an increase for the colloidal (CON) and particulate organic nitrogen (PON) fractions after 28 days of co-digestion were observed. The trend of change was similar for 20% and 80% inoculum. [ABSTRACT FROM AUTHOR]

This study investigates the performance of municipal compost as a heavy metal adsorbent for environmental protection systems. The performed assays test the effects of the pH (2–9) and contact time (5–250 min) on metal retention. To simulate leaching in natural systems, the soluble organic fraction was removed, leading to variations in the surface properties, including a 10% increase in the cation exchange capacity (CEC) and a 242% increase in the BET-specific surface area, accompanied by a small decrease in the surface charge (characterized by a less negative zeta potential values) of the washed municipal compost (WMC). Notably, these variations, which have not been found in previous research, yielded improved retention of Cu(II) and Zn(II) compared to raw municipal compost (RMC), attaining 96% retention for Cu(II) and 97% retention for Zn(II) at a pH of approximately 6.8–7.2 for a contact time of 120 min. The vast availability, cost-effectiveness, and resistance to desorption make municipal compost a viable option in a circular economy context for mitigating metal pollution across various environmental conditions. It is worth noting that this study can serve as a proxy for the expected outcomes in long-term exposure to environmental protection systems, enhancing the practical relevance of using compost for metal retention purposes. [ABSTRACT FROM AUTHOR]

Extracts rich in bioactive compounds from natural sources have received great interest due to their great impact on human health. The aim of this research is focused on the obtaining and characterization of several extracts from Juglans regia L. leaves in four different maturity phases: young green leaves (YGL), green leaves (GL), mature green leaves (MGL), and yellow leaves (YL), using different solvents: ethanol (e), water (w), or water:ethanol (1:1 (v/v)—m) by employing several methods: magnetic stirring (MS), ultrasound-assisted (UA), as well as maceration (M). The obtained extracts were quantitatively evaluated through spectrophotometric methods: Total Polyphenol Content (TPC-Folin–Ciocalteu assay) and Total Antioxidant Capacity (TEAC assay). Phytochemical screening by means of Fourier-Transform Ion–Cyclotron-Resonance High-Resolution Mass Spectrometry (FT-ICR-MS) indicated the presence of 40 compounds belonging to different phytochemical classes: phenolic acids, flavonoids, flavones, flavanones, flavonones, flavanols, vitamins, tereponoid, steroid, anthocyanidin, and other compounds. Based on TPC and TEAC assays, the water-ethanol mixture was found to be the proper extraction solvent, with the best results being obtained for YL plant material: 146.29 mg GAE/g DM (TPC) and 11.67 mM TE/g DM (TEAC). This type of extract may be used in various domains, such as the cosmetics industry, the biomedical field, and/or the design of functional foods, relying on their phytochemical composition. [ABSTRACT FROM AUTHOR]

Residual waste is a key fraction of municipal solid waste generated, yet its management is poorly understood and has gained little attention over the past years. Using London as a case study, the present study analyses the amount of residual waste collected and managed to check on how well ahead the UK is in making progress on achieving the circular economy principles. The study found that 5 Mt of residual waste is reported to be managed in London, of which 3.5 Mt is managed via recovery operations and 1.59 Mt is managed via disposal operations. For the latter, landfills are the principal disposal option taking in 0.82 Mt of residual waste each year. Amongst the recovery options, incineration with energy recovery, is the most prevalent, accounting for the management of 1.44 Mt of residual waste. This highlights the presence of an important technological lock-in that could jeopardise UK’s ability to achieve its net zero carbon ambition. It is worth noting that the data collated and analysed depicts the movements of residual waste rather than its final treatment, pointing to blind spots in the final fate of residual waste as well as potential double counting; both of which prevent decision- and policy-making. Therefore, the need for transparency in data recording and monitoring and the creation of a level playing field for all stakeholders involved in residual waste management are of paramount importance in gradually breaking reliance on destructive treatment processes. This could empower improved segregation of waste at source, and in turn, enable the better management of residual waste. The study underlines that residual waste has a significant role to play in making the transition to a circular economy and therefore is imperative to pave the way for future policy direction on residual waste management. [ABSTRACT FROM AUTHOR]

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Bismuth telluride is the only commercially applied thermoelectric material. The n‐type material is usually prepared by the method of zone melting; however, the utilization ratio of the ingot is relatively low, owing to the bad thermoelectric performance of the two ends. Herein, the waste of n‐type bismuth telluride is recovered by the second zone melting and PbBr2 doping. It is shown that the second zone melting can improve the grain alignment, leading to the increase of carrier mobility. When PbBr2 doping is introduced, lattice thermal conductivity is largely reduced by the high dense dislocations. As a result, the peak power factor and maximum ZT reach 53 μW cm−1 K−2 and 1.15, respectively, which are even higher than the values of the original commercial material. This work provides an economic and applicable strategy to recover the waste of bismuth telluride thermoelectric materials. [ABSTRACT FROM AUTHOR]

The article describes a process based on the hydrogen recovery of dust removal ash from lignite pyrolysis. The high volatile components in lignite will produce a large amount of H2 during the pyrolysis process, which can replace part of C to reduce zinc and iron oxides in dust removal ash, thereby achieving the goal of reducing carbon consumption. Two methods were used to study the different pyrolysis behaviors of lignite, and it was found that the peak of H2 release was reached at 700 °C. After 1000 °C, the pyrolysis of lignite basically ended, and the final pyrolysis gases were mainly H2, CO, CO2, CH4, and a small amount of CxHy. In addition, the proportion of H2 generated by the full pyrolysis of lignite at 1000 °C in H2–H2O is 84.4 %, and the proportion of CO in the CO–CO2 system is 74 %, which can meet the reduction of zinc and iron oxides in dust removal ash. Based on the principle of minimum free energy and laboratory experiments, zinc oxide is completely reduced to zinc vapor above 906 °C, while the Fe obtained from iron oxide reduction increases with the increase of H2/CO in the system above 810 °C, further confirming the feasibility of this process. The effects of temperature, lignite added amount and holding time on iron reduction and zinc volatilization during the reduction process of dust removal ash was investigated. The results indicate that due to the fast diffusion rate of H2, the reaction rate is greatly increased, which can quickly increase the metallization rate of dust removal ash to over 95 % and the dezincification rate also increases from 19.60 % to about 98.76 % with the increase of carbon content under low temperature (1000 °C) and low carbon content (10 wt %) conditions.

The article deals with the problem of waste management in Algeria. It aims to analyze the various policies undertaken by the government in order to be able to respond to the principles of sustainable development and the circular economy from the perspective of sustainable and integrated waste management. The analyses carried out show that the first waste management strategies in Algeria are more reactive and constitute a response to the crisis of the proliferation of waste. It is only from the year 2016 that the national integrated waste management strategy constitutes a perspective of registration of this sector in a circular approach of profitability and sustainability.

Recycling aluminium is essential for a circular economy, reducing the energy required and greenhouse gas emissions compared to extraction from virgin ore. A 'Twitch' waste stream is a mix of shredded wrought and cast aluminium. Wrought must be separated before recycling to prevent contamination from the impurities present in the cast. In this paper, we demonstrate magnetic induction spectroscopy (MIS) to classify wrought from cast aluminium. MIS measures the scattering of an oscillating magnetic field to characterise a material. The conductivity difference between cast and wrought makes it a promising choice for MIS. We first show how wrought can be classified on a laboratory system with 89.66% recovery and 94.96% purity. We then implement the first industrial MIS material recovery solution for sorting Twitch, combining our sensors with a commercial-scale separator system. The industrial system did not reflect the laboratory results. The analysis found three areas of reduced performance: (1) metal pieces correctly classified by one sensor were misclassified by adjacent sensors that only captured part of the metal; (2) the metal surface facing the sensor can produce different classification results; and (3) the choice of machine learning algorithm is significant with artificial neural networks producing the best results on unseen data. [ABSTRACT FROM AUTHOR]