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The paper explores challenges arising from the existence of expansive clay soils, renowned for causing structural damage and exhibiting detrimental environmental effects. Implementing a novel approach, this study introduces the use of fly ash (Class F) and shredded face masks (FMs) to enhance soil properties. Fly ash (FA), known for its pozzolanic properties, is combined with shredded waste FMs to reinforce the soil. Remolded specimens underwent comprehensive laboratory testing, including Unconfined Compressive Strength (UCS), California Bearing Ratio (CBR), Swell Test, Consolidation Test, and Triaxial Test. The optimal blend identified as 0.9% FMs + 20% FA achieves an optimal equilibrium of strength, stability, and reduction in swelling. The UCS exhibited an increase with the addition of FA, and this improvement was further enhanced with the inclusion of 0.9% FMs, surpassing the specified subgrade CBR values. The percentage of swell exhibited a notable decrease from 5.9% to 1.8% with the incorporation of FA + FMs. This sustainable approach aims to conserve valuable resources and mitigate challenges associated with waste disposal along with the economic benefits to contribute to achieve UN SDGs 2030. [ABSTRACT FROM AUTHOR]

In this study, carbon material obtained from sunflower seed shells and doped with Fe and Zn using mint extract (Fe-Zn-SSSC) was prepared, and the usability of this adsorbent in the removal of paracetamol, diclofenac sodium, and tetracycline was investigated. Fe-Zn-SSSC was characterized by SEM-EDX and FTIR. Additionally, the effects of pH and adsorbent dosage on the removal of paracetamol, diclofenac sodium, and tetracycline were investigated. The removal rates of paracetamol, diclofenac sodium, and tetracycline were obtained as 88.7%, 65.4%, and 76.0% at a pH of 4, after 1 hour of adsorption with 5 g/L Fe-Zn-SSSC, respectively. The best removal of paracetamol, diclofenac sodium, and tetracycline was obtained at pH 4, with qmax values calculated as 14.51 mg/g, 6.33 mg/g, and 8.99 mg/g, respectively. It was determined that the adsorption of paracetamol, diclofenac sodium, and tetracycline with Fe-Zn-SSSC was more compatible with the Langmuir isotherm model and pseudo-second-order kinetic model. As a result, this study demonstrates that carbon materials synthesized from sunflower seed shells can serve as an effective and low-cost adsorbent for drug from water. [ABSTRACT FROM AUTHOR]

Pulp and paper mill sludge is composed of cellulosic waste and clay and is rich in microorganisms that can benefit horticulture. However, its application in horticulture has received less research attention. Field and greenhouse studies were carried out to determine if sludge from a case study industry can replace the typical cellulosic additive utilized in hydroseeding, and the ideal application rate of a sludge-soil-seed mixture. The treatments were 0–100% sludge and soil by mass with a consistent mass of embedded seeds of Kentucky Bluegrass (Poa pratensis), Creeping Red Fescue (Festuca rubra), Perennial (Lolium perenne) and Annual Ryegrass (Lolium multiflorum). Seeding with a top layer of soil and 5 to 75% sludge gave the best outcome using a cellulosic additive after 3 weeks of growth. Mixtures containing 5–25% sludge resulted in the quickest seed germination rate. The cellulosic additive has the capacity to retain a higher volume of water but requires 15 times more material by volume. An increase in sludge increased water retention by 20%. Overall, the cellulosic additive in hydroseeding applications can be replaced by sludge without plant detriment. However, further testing is needed to determine long-term effects. Highlights: Paper mill sludge exhibited evidence of slow-release fertilizer behavior. Germination rate increased in the presence of slow percentages of sludge by mass. Grass demonstrated the capacity to be grown in 100% sludge. Paper mill sludge showed potential to replace the typically cellulosic additive in hydroseeding mixtures. [ABSTRACT FROM AUTHOR]

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This study aimed to develop eco-friendly limestone calcined clay cement (LC3)-based lightweight bricks by reusing waste rockwool (RW) with the improvement of technical performances such as thermo-physical and mechanical, including fire-resistance performances. LC3 binder was blended with expanded clay (EC) aggregates at a ratio of binder-to-aggregate of 1:1.5 (vol%). EC was substituted by waste RW at different percentages, ranging from 5 to 15 vol%. Several technical properties such as density, compressive strength, total porosity, water absorption, thermal conductivity, and thermal diffusivity were investigated after 7 days of curing. The fire-resistance performance of the developed bricks was determined by assessing the residual compressive strength after exposure to standard fire for up to an hour. With dry bulk densities ranging from 1200 to 1360 kg/m3 and compressive strengths (>8.60 MPa), the developed brick met the acceptance criteria for non-load-bearing applications. Even at the highest dosage of RW, the results demonstrated a thermal conductivity as low as 0.36 W/mK, indicating that the developed brick is suitable for hot weather zones, as it reduces the heat flow into buildings. The partial replacement of EC by RW is very beneficial in enhancing the fire-resistance performance, and a residual strength of about 89.7% has been maintained by the bricks incorporating 5% waste RW after 1 h of fire exposure (employing a maximum applied temperature of 927 °C). Lifecycle assessment results indicated that up to 13% lower carbon emissions are associated with LC3-based lightweight bricks designed to reuse a higher amount of waste RW. [ABSTRACT FROM AUTHOR]

Biomass activated carbon regeneration technology is widely used for environmental treatment and resource recovery. Various regeneration methods are available, including thermal, chemical, microwave, electrochemical, biological, wet oxidation, supercritical fluid, and ozone regeneration. Among these methods, thermal regeneration is the most widely used. Chemical regeneration is a simple and cost-effective option. Microwave regeneration allows for accurate control of regeneration parameters and quick processing of spent activated carbon. Electrochemical regeneration can be operated at low temperatures and has good regeneration stability. Biological regeneration technology is a more environmentally friendly option as it can reduce the use of chemicals. Wet oxidation regeneration technology can treat activated carbon with less loss of quality and lower energy consumption. Supercritical fluid regeneration technology uses recyclable and non-polluting solvents. Ozone technology is another option for regenerating spent activated carbon at room temperature and pressure, which can be beneficial for the process economics. The article reviews these technologies and provides an analysis of each method′s regeneration mechanism, technical characteristics, and current research status.

This study collected sludge samples from the kraft pulp mills of a Brazilian industry and physicochemically characterized them to investigate their biovalorization. The objective was to identify opportunities to produce value-added products, promoting the circular economy and environmentally appropriate destinations. The types of processes and raw materials influence sludge characteristics. The primary sludge was composed mainly of fibers and water, has a slightly alkaline pH, Carbon:Nitrogen (C:N) ratio is high attributed to fibers, and contains calcium, magnesium, phosphorus, and organic carbon. The biological sludge was rich in proteins, bacterial cells, and minerals. The analyses revealed functional groups such as hydroxyls and aliphatic methylene, high concentrations of carbon and oxygen, a fibrous and crystalline structure of cellulose in the primary sludge, and dense microparticles in the biological sludge. Thermogravimetry found a mass loss of 11 % and final combustion at 742 °C for the biological sludge. The primary sludge showed a mass loss of 38 % with peaks at 329 and 784 °C, which suggests that the primary sludge could be used as fuel. Potential routes for the use of the primary and biological sludge included its use as agricultural fertilizer, thermal processing, biochar, and production of activated carbon, despite the low calorific values. [ABSTRACT FROM AUTHOR]

The development of new sound absorbing materials and the transition to net zero emissions production have become inseparable. This paper investigates a new type of composite sound absorbing material made of waste tyre textile fibre (WTTF) and different binders: polyurethane resin (PU), polyvinyl acetate (PVA), and starch (POS). Non-acoustic and acoustic parameters were studied, and life cycle assessment was performed for the considered composite sound absorbing materials. The airflow resistivity was determined according to the ISO 9053-1 standard, while the sound absorption coefficient was determined according to the ISO 10534-2 standard, and the LCA was performed based on the ISO 14040 and ISO 14044 standards. Composite sound absorbing materials subjected to sound absorption coefficient tests showed results in the range of 0.04 to 0.99 and peaking in the frequency range of 800 to 2000 Hz, while airflow resistivity varied between 17.4 and 83.6 kPa⋅s/m2. The combination that gave the highest sound absorption coefficient was experimentally found to be PU composite material. Life cycle assessment results revealed that the lowest potential impact on the environment is obtained when composite materials are produced using starch as a binder and its total potential impact on the environment varied between 0.27 and 0.55 Pt, while the highest potential impact was observed by PU composites (0.33 ÷ 0.64 Pt). The results obtained experimentally and by LCA modelling revealed great attractiveness and promising development of composites using WTTF and different binders' potential for sound absorbing applications. [ABSTRACT FROM AUTHOR]

Recent disasters involving upstream raised tailings dams in Brazil have caused regulatory agencies to prohibit the construction of new upstream dams and demand the decommissioning of existing ones. As such, new alternatives are being sought to safely dispose of iron ore exploitation byproducts. The dry stacking of filtered tailings is an option to diminish the risks associated with tailings storage facilities and cope with new legislation. Accordingly, this paper studies new solutions for enhancing the performance of tailings for dry stacking purposes. The behavior of reinforced and nonreinforced iron ore tailings-alkaline-activated cement (AAC) blends was studied through unconfined compressive strength tests and conventional triaxial testing. The AAC is produced from the residues of iron ore exploitation (waste and tailings). The addition of fibers has enhanced the performance of cemented iron ore tailings with increased strength regardless of the fiber content and ductility. Also, reinforcement effectiveness values were greater than those reported for other cement agents, due to the lower stiffness of the cemented matrix from AAC compared with others. A comparative analysis between using only AAC and ACC plus 0.5% of fibers within the η/Biv framework was proposed. The dosage curves for the same qu value yielded an AAC=20.80% for AAC only and AAC=3.80% when using 0.5% of fibers. Therefore, using fibers can collaborate with the feasibility of using a new waste-based AAC to construct dry stacking facilities. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate biochar produced from eggshells to remove water-polluting substances and to apply it on clayey soil to improve physical properties. CCRD was used to determine the influence of biochar concentration and contact time in water-polluting substance removal. Bacteria removal efficiency and genotoxicity effects were evaluated. Compaction and compressive strength tests were performed after the application of biochar to clayey soils. The removal efficiency of aluminum, fluoride, manganese, zinc, and iron were 52.8, 69.8, 78.9, 96.7, and 96.4%, respectively. After 6 h of contact time, E. coli was completely removed. The water did not demonstrate genotoxic residual after biochar application. The maximum compressive strength obtained demonstrated an increase of 29.7% if compared to control. The biochar production from eggshell waste to remove water-polluting and stabilization of clayey soil provides a very simple, low-cost, effective and environmental friendly of this waste. [ABSTRACT FROM AUTHOR]

The considerable amount of solid residue generated by the common effluent treatment plant (CETP) of tanneries needs adequate treatment and reclamation before ending up in the environment as solid waste. A sustainable process aiming at tannery CETP waste minimisation and its reuse for sodium chloride salt recovery is presented. The integrated approach consists of dissolution, decolorisation, filtration, evaporation, and crystallization as unit operations. Lab-scale parametric studies have been undertaken to investigate the effects of various parameters at different process stages on product (sodium chloride) yield and quality. The developed process resulted in the recovery of 93% NaCl, having a purity of ∼98.5%. The optimised operating conditions were tested on a bench-scale system (15 kg batch scale of solid residue) deploying solar energy for evaporation-crystallization, and process feasibility was established. An economic analysis was performed, and the techno-economic feasibility was demonstrated to produce 15,733 tons per annum (TPA) of NaCl from 20,000 TPA of solid residue. The techno-economic analysis favours the treatment of tannery CETP waste with the method specified. The proposed scheme can tackle waste management and reuse the recovered product in the tanning process. [ABSTRACT FROM AUTHOR]

This study aimed to develop eco-friendly limestone calcined clay cement (LC3)-based lightweight bricks by reusing waste rockwool (RW) with the improvement of technical performances such as thermo-physical and mechanical, including fire-resistance performances. LC3 binder was blended with expanded clay (EC) aggregates at a ratio of binder-to-aggregate of 1:1.5 (vol%). EC was substituted by waste RW at different percentages, ranging from 5 to 15 vol%. Several technical properties such as density, compressive strength, total porosity, water absorption, thermal conductivity, and thermal diffusivity were investigated after 7 days of curing. The fire-resistance performance of the developed bricks was determined by assessing the residual compressive strength after exposure to standard fire for up to an hour. With dry bulk densities ranging from 1200 to 1360 kg/m3 and compressive strengths (>8.60 MPa), the developed brick met the acceptance criteria for non-load-bearing applications. Even at the highest dosage of RW, the results demonstrated a thermal conductivity as low as 0.36 W/mK, indicating that the developed brick is suitable for hot weather zones, as it reduces the heat flow into buildings. The partial replacement of EC by RW is very beneficial in enhancing the fire-resistance performance, and a residual strength of about 89.7% has been maintained by the bricks incorporating 5% waste RW after 1 h of fire exposure (employing a maximum applied temperature of 927 °C). Lifecycle assessment results indicated that up to 13% lower carbon emissions are associated with LC3-based lightweight bricks designed to reuse a higher amount of waste RW.

By 2050, the world's population is predicted to reach over 9 billion, which requires 70% increased production in agriculture and food industries to meet demand. This presents a significant challenge for the agri-food sector in all aspects. Agro-industrial wastes are rich in bioactive substances and other medicinal properties. They can be used as a different source for manufacturing products like biogas, biofuels, mushrooms, and tempeh, the primary ingredients in various studies and businesses. Increased importance is placed on resource recovery, recycling, and reusing (RRR) any waste using advanced technology like IoT and artificial intelligence. AI algorithms offer alternate, creative methods for managing agro-industrial waste management (AIWM). There are contradictions and a need to understand how AI technologies work regarding their application to AIWM. This research studies the application of AI-based technology for the various areas of AIWM. The current work aims to discover AI-based models for forecasting the generation and recycling of AIWM waste. Research shows that agro-industrial waste generation has increased worldwide. Infrastructure needs to be upgraded and improved by adapting AI technology to maintain a balance between socioeconomic structures. The study focused on AI's social and economic impacts and the benefits, challenges, and future work in AIWM. The present research will increase recycling and reproduction with a balance of cost, efficiency, and human resources consumption in agro-industrial waste management. [ABSTRACT FROM AUTHOR]

Olive mill waste (OMW) is a promising source of valuable compounds such as polyphenols, terpenes, sterols, and other bioactive compounds, which are of interest to the pharmaceuticals and cosmeceutical industries. This review examines the potential of OMW extracts for health and beauty applications based on evidence reports from human clinical trials. The results achieved to date indicate health‐enhancing properties, but little is known about the underlying mechanisms of action, dose–response relationships, and long‐term impacts. Therefore, while olive by‐products, extracted using eco‐friendly methods, present opportunities for the development of high‐value health and cosmetic products, further studies are necessary to determine the full range of their effects and establish specific therapeutic strategies. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present work developed a thermal insulating coating/plastering mortar from the complete replacement of the natural aggregate by friable quartzite (QTZ), with the addition of steelmaking slag powder (SSP). Despite having promising characteristics, no studies so far have taken advantage of the thermal insulating properties of the SSP. Initially, the QTZ and PEA were characterized according to physical, chemical, mineralogical, and morphological analyses. The mortars were prepared with Portland cement, hydrated lime, air-entraining admixtures (AEA), fine aggregates, and SSP. Four mixes were produced: (1) reference (REF) (with natural sand); (2) QTZ + AEA (NO SSP); (3) QTZ + AEA + 5%SSP, and (4) QTZ + AEA + 10%SSP. The following tests were carried out: flow, water retention, specific gravity (density), water absorption by immersion and by capillarity, flexural strength, compressive strength, adhesive strength, UPV, morphology, shrinkage, thermal conductivity, specific heat, and potential of environmental contamination. As result, the QTZ presented physical characteristics similar to those of the natural aggregate, except for the high content of powdery material. The mortar with 5% SSP had the lowest thermal conductivity (56% lower than REF) and the highest specific heat (37% higher than REF). The SSP's mineralogical composition and resulting pore system were the most influential factors for these properties. Therefore, the SSP can be considered a "thermal insulating admixture" and the use of these residues is technically feasible to improve the thermal performance of buildings. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic disrupted global food waste patterns through unanticipated shifts in composition and quantities. This review explores the impacts of COVID-19 on food waste generation and management approaches in the Near East and North Africa (NENA) region during the recovery phase. This paper comprehensively explores food loss and waste in the NENA region. It presents a detailed analysis of pandemic-induced changes in household food waste behaviors, analyses the integration of circular economy principles in recovery strategies and policy implications, and outlines potential avenues for future research in this critical area. The key findings are threefold: First, this study reaffirms that food waste is a critical challenge in NENA, contributing to food insecurity, water scarcity, and environmental issues. Second, the pandemic catalyzed a dichotomy in consumer behaviors—panic buying initially increased waste, while hardship measures later encouraged sustainable waste reduction practices like meal planning and leftover use. Third, adopting a circular economy approach holds potential, yet its implementation remains limited in terms of curbing food waste and promoting sustainability in NENA. Overall, while the pandemic accentuated the urgency of tackling food waste, it also stimulated innovative policy thinking and strategic planning for building more resilient food systems. This paper concludes that leveraging pandemic-driven sustainability mindsets while addressing systemic drivers of waste will be key to mitigating food waste and its impacts moving forward. This paper offers timely insights into the evolving food waste management landscape in NENA, underscoring the need for integrated policies to navigate post-pandemic recovery effectively. [ABSTRACT FROM AUTHOR]

The Circular Economy emerges as an alternative to reinvent the linear production model (take–make–waste), focusing on reintegrating waste into the production cycle, and aiming to minimize both environmental disposal and the unrestrained extraction of raw materials. In this context, the concept of Blue Economy arises, an approach centered on preserving and valorizing marine and coastal resources. This article aims to develop a model for the circuit of bivalve shells, emphasizing the transformation of the residues into new products and identifying how these processes affect sociocultural, economic, and environmental dimensions. The methodology involved the surveying of local stakeholders directly involved in bivalve production and consumption to identify the relationship of these stakeholders with the production, marketing, and disposal of bivalves. It is concluded that biowaste has potential, and there is interest among local stakeholders in reusing it, but a lack of knowledge and connection among stakeholders ultimately leads to the devaluation of the product. The circuit of bivalves is necessary to identify value, propose correct collection, and stimulate interest in their reuse, both by other industries and by the aquaculture industry itself. Exploring the potential for reusing bivalves and mitigating their waste, as well as preventing improper disposal, could drive the development of the Blue Circular Economy in coastal regions. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although there has been considerable research on the utilization of ceramic and tile waste (CTW) in concrete production, there has been a noticeable lack of studies examining its application in fired brick manufacturing and the use of ceramic glaze powder as an additive in cement. The aim of this study is to assess the potential of reusing CTW as concrete aggregate and as part of fired brick composition. Furthermore, this research investigates the potential application of glaze powder as a novel cement additive, which has not been previously explored. RESULTS: The results indicate that bricks made from waste materials had a moisture absorption of 12.2% and flexural strengths ranging from 15.39 to 24.2 MPa. X‐ray diffraction analysis showed that quartz and kaolinite were the dominant crystalline phases in bricks made from raw glazed ceramic. The concentration of heavy metals in the toxicity characteristic leaching procedure leachate of the waste materials decreased after the firing process during the manufacturing of bricks due to oxidation, immobilization and encapsulation processes, with levels below standard limits. In concrete, the use of 20% ceramic glaze powder as a partial cement replacement resulted in a 55% increase in compressive strength. Additionally, the leaching of barium decreased by 70% and that of strontium decreased by 17%. CONCLUSION: This study highlights the promising utilization of CTW in fired brick production and the effective incorporation of ceramic glaze powder as a cement additive. The findings suggest enhanced mechanical properties and decreased heavy metal leaching, indicating the viability of CTW reuse in sustainable construction practices. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

This study investigates the engineering behavior of a sustainable geomaterial called Pond Ash Geomaterial (PAGM), made by blending Expanded Polystyrene beads (EPS) with pond ash and cement as a binding agent. The effects of EPS density, beads content, and cement content on the density, compressive strength, and elasticity modulus of PAGM are analyzed. The results show that PAGM with low-density and low-content EPS can achieve similar properties to high-density and high-content EPS PAGM. Based on these findings, design charts are proposed that can facilitate the guidelines for the application of PAGM on-site. The study highlights the suitability of PAGM as a lightweight filling material that can reduce environmental impact and be a cost-effective alternative to EPS geofoam blocks. Predictive models are developed for determining the engineering characteristics of the PAGM. Overall, the use of PAGM as a building material has practical implications for sustainable construction practices, as it utilizes an industrial byproduct, reduces waste, and can be used in a range of applications.

Despite the polluting potential olive mill wastewater (OMW) can be a useful source of nutrients and organic compounds to improve soil properties. The aim of this paper was to verify if biochar-based treatment of OMW could be an efficient method to contrast the richness in phenolic compounds and phytotoxicity of OMW making it more suitable. for soil amendment. In this study poplar biochar (BP) was more effective than conifer biochar (BC) in terms of adsorbing phenols and reducing phytotoxicity at different biochar rates (5 and 10 %). In soil amendment BP-treated OMW induced an increase of organic carbon by approximately 15 % and notably BP10 treated OMW enhanced available phosphorous by 25 % after 30 days of incubation. In soil amended with 10 % BP-treated OMW microbial biomass and enzymatic activities were significantly enhanced after 30 and 90 days, with no effect on cress seed germination. Therefore, biochar based-treatment could be cost-effective and able to facilitate the long-term management of OMW in terms of storage and disposal.

With the rapid development of urbanization, the number of urban sewage treatment plants is increasing, wastewater treatment volume is gradually becoming large, and correspondingly, the sludge production capacity has a rapid growth. As a new method of sludge disposal, sludge carbonization is characterized by low energy consumption, simple products, and wide resource utilization prospects, which is of great help to solve problems of current sludge disposal in China. The residual sludge from sewage plant was used as raw material in this study in order to investigate the physical and chemical properties of sludge charcoal after high temperature carbonization and explore the enhancement in the removal of pollutants including CODcr, NH3-N, TN, and TP during sewage treatment with the used sludge charcoal. The results show that the optimal dosing amount of sludge charcoal was 2 g.L−1 when it was added into SBR equipment at one time, while the optimal dosing amount is 0.06 g.L−1 when it was added into SBR equipment with each influent process. The enhanced removal effect of pollutants in sewage treatment process mainly depended on the physical adsorption and intensified bio-degradation of sludge charcoal, and activated sludge and sludge charcoal were synergistic in water treatment. The removal effect of pollutants is strengthened in the physical adsorption—bio-degradation—sludge charcoal reproduction—re-adsorption system. These suggested that sludge charcoal could be promising for the enhancement of pollutant removal in sewage through activated sludge process. [ABSTRACT FROM AUTHOR]

Composite materials are used in a substantial number of products. Environmental concerns highlight the need for the inclusion of recovered waste in their formulation, thus reducing their carbon footprint. These solutions raise the need to confirm the mechanical characteristics of these materials, avoiding unwanted failures. In this work, the authors present an experimental study on the drilling effects on fibrous–particulate hybrid composites made of glass/carbon fabrics and three different micro-inclusions: silica particles, recycled carbon fibre powder and cement. The mechanical features of the plates are confirmed by thrust force monitoring during drilling and by flexural testing. The range of results confirm the mechanical outcomes due to machining. The plates with monolithic carbon fabric or with carbon fabric plies in the outer plies returned higher mechanical characteristics. The plates with micro-inclusions had enhanced the flexural strength by 23% and 10%, in 40% and 60% fabric plates, respectively. The results demonstrate that the use of alternative formulations with micro-inclusions from recovered waste can contribute both to the reduction of the mechanical degradation of drilled hybrid composites and to environmental purposes by avoiding the increase in landfill waste. [ABSTRACT FROM AUTHOR]

Abstract Background The soil microbiota has a direct impact on plant development and other metabolic systems, such as the degradation of organic matter and the availability of microelements and metabolites. In the context of agricultural soils, microbial activity is crucial for maintaining soil health and productivity. Thus, the present study aimed to identify, characterize, and quantify the microbial communities of four types of substrates with varying proportions of marine port sediment used for cultivating lemons. By investigating microbial diversity and relative abundance, the work aimed to highlight the importance of soil microbial communities in agriculture when alternative culture media was used. Results The composition and structure of the sampled microbial communities were assessed through the amplification and sequencing of the V3-V4 variable regions of the 16 S rRNA gene The results revealed a diverse microbial community composition in all substrate samples, with a total of 41 phyla, 113 classes, 266 orders, 405 families, 715 genera, and 1513 species identified. Among these, Proteobacteria, Bacteroidota, Planctomycetota, Patescibacteria, Chloroflexi, Actinobacteriota, Acidobacteriota, Verrucomicrobiota, and Gemmatimonadota accounted for over 90% of the bacterial reads, indicating their dominance in the substrates. Conclusions The impact of the substrate origin on the diversity and relative abundace of the microbiota was confirmed. The higher content of beneficial bacterial communities for plant development identified in peat could explain why is considered an ideal agricultural substrate. Development of “beneficial for plants” bacterial communities in alternative agricultural substrates, regardless of the edaphic characteristics, opens the possibility of studying the forced and specific inoculation of these culture media aiming to be agriculturally ideals.

Life cycle assessment (LCA) is a methodology that has been widely used to evaluate the environmental impact of products and processes throughout entire life cycles. In this context, the reuse of waste in paved road construction is a practice that has received increasing attention as a sustainable alternative to solid waste disposal. This article presents a systematic review of existing studies on the LCA of paved roads that incorporate waste reuse and proposes a guideline for LCA in this context. Several criteria were analyzed in the articles, and the results showed that only 5% of the articles followed all the recommendations set out in ISO 14040. The proposed guideline aims to provide guidance for future research and includes recommendations for each of the steps involved in LCA, from defining the objectives and scope of the study to interpreting the results. [ABSTRACT FROM AUTHOR]

Challenges posed by industrial solid waste, particularly Electrical Cable Waste (ECW), have been increasingly recognized due to their environmental implications and substantial decomposition timelines. ECW, a byproduct of aggressive demolition and reconstruction in Iraq, has seen limited investigation regarding its potential use as an aggregate substitute and fiber additive in concrete applications. This study endeavors to repurpose ECW as a partial replacement for natural sand and as fiber reinforcement, with a focus on both short-term and long-term performance. A fixed ratio of natural sand was substituted with ECW (10%), and waste fibers were integrated at varying concentrations (0.5%, 1%, 1.5%, 2%, 2.5%, and 3%). For comparative purposes, a control mix devoid of ECW and fibers was also examined. Evaluations were conducted on the flow rate, along with compressive strength, flexural strength, and density at intervals of 7, 28, and 360 days. Results indicate that despite a reduction in flowability and a decrease in hardened density to under 2000 kg/m3, inclusion of ECW can yield a sustainable lightweight mortar without significant compromise on strength. This study thus underscores the potential of waste repurposing as a viable solution for waste management and environmental enhancement. Additionally, this approach can help mitigate natural resource depletion, such as that of natural sand, fostering a move towards sustainable construction practices. [ABSTRACT FROM AUTHOR]

In a contemporary sustainable economy, innovation is a prerequisite to recycling waste into new efficient materials designed to minimize pollution and conserve non-renewable natural resources. Using an innovative approach to remediating metal-polluted water, in this study, eggshell waste was used to prepare two new low-cost nanoadsorbents for the retrieval of nickel from aqueous solutions. Scanning electron microscopy (SEM) results show that in the first eggshell–zeolite (EZ) adsorbent, the zeolite nanoparticles were loaded in the eggshell pores. The preparation for the second (iron(III) oxide-hydroxide)–eggshell–zeolite (FEZ) nanoadsorbent led to double functionalization of the eggshell base with the zeolite nanoparticles, upon simultaneous loading of the pores of the eggshell and zeolite surface with FeOOH particles. Structural modification of the eggshell led to a significant increase in the specific surface, as confirmed using BET analysis. These features enabled the composite EZ and FEZ to remove nickel from aqueous solutions with high performance and adsorption capacities of 321.1 mg/g and 287.9 mg/g, respectively. The results indicate that nickel adsorption on EZ and FEZ is a multimolecular layer, spontaneous, and endothermic process. Concomitantly, the desorption results reflect the high reusability of these two nanomaterials, collectively suggesting the use of waste in the design of new, low-cost, and highly efficient composite nanoadsorbents for environmental bioremediation. [ABSTRACT FROM AUTHOR]

This study investigated the possibility of using the spent kind of biomass of Pseudomonas putida CA-3 and Zobelella denitrificans MW1 obtained after the pilot-scale production of polyhydroxyalkanoates (PHAs) as a biosorbent for the bioremediation of aqueous solutions containing toxic cadmium and lead ions. The material was characterized by means of scanning electron microscopy, Fourier-transformed infrared spectroscopy, nuclear magnetic resonance spectroscopy and amino acid profiling. To check the sorption capacity of spent biomass against Pb and Cd ions, equilibrium studies were performed. To learn about the nature of the sorption process, kinetic modelling was carried out and the obtained results showed that the adsorption process is best described by the pseudo-second-order kinetic model (PSO), which suggests that the sorption process is connected with the chemical bonding of the ions on the sorbent surface. Information provided by the amino acid profile made it possible to predict the adsorption mechanism and FTIR analysis proved the participation of different chemical groups in the removal process. According to the equilibrium studies, the best-fitted isotherm was the Freundlich model for all used materials and metal ions considering the correlation coefficient. Summarizing the results, the spent biomass after the PHA production is an effective biosorbent and can be reused for heavy metal bioremediation. [ABSTRACT FROM AUTHOR]