Search

The extensive use of external thermal insulation composite systems (ETICS) using expanded polystyrene (EPS) for building insulation in Germany has resulted in accumulating end-of-life EPS-ETICS. To address limited waste management options and enhance EPS circularity, alternative recycling options like pyrolysis or solvent-based recycling need to be implemented. However, efficient recycling requires ex-ante analyses of the corresponding reverse logistics networks, including all necessary pre-treatment and transport processes. This study aims to develop a decision support system to determine optimal EPS-ETICS waste management by minimising the net present value of the corresponding network design. Our mixed-integer linear optimisation model considers decisions on technology, capacity, and location for pre-processing and recycling facilities as well as on material flow allocation. Applied to a German case study, our model finds pyrolysis and solvent-based recycling economically superior to current waste treatment in waste incineration plants. We present an optimal network design combining central pyrolysis with decentral pre-processing. A scenario analysis shows fluctuating styrene and polystyrene prices might favour solvent-based recycling over the optimal choice in pyrolysis, with minor overall cost differences. Further, legal recycling quotas of at least 40% would be necessary to promote solvent-based recycling and enhance EPS circularity beyond what is achievable through pyrolysis. [ABSTRACT FROM AUTHOR]

The article presents the results of analytical and experimental investigations, as well as modeling of the ingotless rolling-extrusion (IRE) process for thermal deformation treatment of secondary waste of the extrusion production made of alloy 6063. Using the QForm software package and analytical calculations, the temperature–velocity and energy-force parameters of the IRE process for obtaining ligature rods with a diameter of 9 mm from waste of the investigated alloy were determined. In the course of experimental studies pilot, lots of such rods were obtained. The process parameters for rods production by the IRE method were specified and investigations of their structure and properties were carried out. In this case, the melt temperature was 750 ± 10 °C; the temperature of the crystallized billet was 520 °C; the roll rotation frequency was 5 rpm; the strain during rolling was 50%. Rods obtained from waste from the extrusion production of alloy 6063 by the IRE method have a stable ultra-fine subgrain structure. Analysis of the properties in comparison with a rod obtained by hot extrusion revealed higher plastic characteristics and full compliance with the requirements of the standard in force at the production site. [ABSTRACT FROM AUTHOR]

Development of a cost‐effective and environmentally friendly method to treat dye wastewater is of utmost importance. In this experimental study, wastepaper was used as the raw material for the extraction of cellulose nanocrystals to fabricate a nanocomposite membrane with chitosan. During the extraction process, acid hydrolysis (Sulfuric acid) followed by bleaching (hydrogen peroxide) was adopted. To confirm the nano‐range, particle size analysis, and FESEM were performed, which confirmed the presence of particles in the nano‐range ranging from 313.8 to 122.1 nm and FESEM observed results showed transformation of fibrous to rod shaped nanocrystals after acid hydrolysis. After successful nanocomposite fabrication a porous sieved network of membrane was observed and after adsorption successful adhesion of dye molecules over the membrane matrix was also confirmed. FTIR data showed that during adsorption mechanism some of the prominent peaks gets disappeared suggest interaction of dye molecules onto the nanocomposite. The contact angle of 21.0° was observed for the ChNC3 nanocomposite showed super hydrophilic behavior. Tensile strength was also observed in terms of young's modulus, ultimate strength, and elongation at break. The elasticity and stiffness of a material are usually indicated by its young modulus. In AH CNCs and ChNC3, the young modulus was seen to be increasing from 195< 693, respectively. On the other hand, the ultimate strength indicates AH CNCs and ChNC3 and shows a downward trend of 1.56> 0.316, respectively. Furthermore, the potentiality of the nanocomposite membrane was analyzed for Congo red dye in synthetic wastewater prepared in the laboratory. During the batch study, various working parameters were taken such as initial dye solution (20–100 ppm), pH (1–7), contact time (10–60 min), and dosage (0.1–0.5 mg/L). To know about adsorption, Langmuir and Freundlich isotherm were analyzed it was observed that Freundlich isotherm show best fitted modeling with R2 = 0.99, and n = 1.6 showing favorability of the heterogeneous adsorption. To determine the interaction between the adsorbate and adsorbent, pseudo first order and pseudo second order kinetics models were analyzed, and it was observed that chemisorption interaction followed between the adsorbate and adsorbent. Thermodynamic parameters were analyzed, which confirmed the spontaneous and favorable adsorption mechanism. To avoid fouling problems and maintain cost effectiveness, the resulting, nanocomposite membrane was desorbed using an appropriate solvent. After 5 cycles, the desorption rate decreased from 54% to 38%. This developed nanocomposite membrane appears to be effective in effluent waste treatment because of its simple formulation approach. [ABSTRACT FROM AUTHOR]

Whey, a cheese production byproduct, can be anaerobically digested to reduce pollution and generate energy. Yet, stability is challenging due to organic content sensitivity and influent fluctuations. The present work attempts to implement the mechanistic model and machine learning (ML) models (support vector regression (SVR) and artificial neural networks (ANNs)) together to predict the concentration dataset of substrate 1 (S1) (i.e., carbohydrates and proteins), substrate 2 (S2) (i.e., glucids and amino acids), VFA, and methane (CH4) as a function of input independent variables, namely time and organic loading rate (OLR). The R2 values for S1, S2, VFA, and CH4 obtained through the mechanistic model remained as 0.953, 0.918, 0.84, and 0.976, respectively; for ANN models, 0.982, 0.928, 0.958, and 0.99; and for SVR models, 0.984, 0.939, 0.938, and 0.999, respectively. ML models have been discovered to be among the most precise and versatile compared to the mechanistic model. Moreover, other performance metrics, such as RMSE (0.022–2.177), MRE (0.007–0.100), and AARE (0.008–0.104) for ANN and RMSE (0.083–1.961), MRE (0.021–0.091), and AARE (0.037–0.089) for SVR, are obtained, indicating good prediction performances for both ML models. SVR and ANN models excel, aligning concentration curves to the optimum line when input parameters are adjusted, unlike the subpar traditional-based mechanistic model. Therefore, ML methods offer a tool to predict anaerobic digestion more effectively, enhancing design and operations. [ABSTRACT FROM AUTHOR]

This study applies multicriteria mathematical modeling to optimize municipal solid waste (MSW) management across a three bottom-line (BL) framework: environmental, social and economic. The interrelationships and the ripple secondary impacts among the three BLs are examined systematically using an augmented simplex lattice mixture (ASLM) method. Detailed waste and waste treatments, including pyrolysis (PY), anaerobic digestion (AD), animal feed (AF), composting (CP), recycling (RE), incineration (INC) and landfilling (LF), are constructed based on waste stream fractions and treatment allowable limits. The environmental BL is assessed using life cycle assessment (LCA). The economic BL is determined by calculating the per ton capital recovery with return, and the social bottom line is assessed using the analytic hierarchy process (AHP). The three bottom lines are optimized through a mathematical model using CPLEX solver. The results indicate that CP abates 973 kgCO2eq/t compared to 61.8 kgCO2eq/t from AD and 28.3 kgCO2eq/t from AF. CP generates $23.5/t despite its low social desirability. Plastic waste PY credits ethylene by 364 kg/t, however, it costs $226.7/t despite the subtraction of credited energy and recovered byproducts. Metal RE carbon and water footprints are −236 kgCO2eq/t and 268 m3/t, respectively. AF is the second-best economic scenario after metal RE as it generates up to $122.6/t in profit. AF production scores are second highest within the social BL after plastic PY; however, the supporting legislation sub-indicator is low. The ASLM support policy that assigns 66% to the environmental BL and 16.7% to the economic and social BL to achieve carbon neutrality within the MSW sector. [ABSTRACT FROM AUTHOR]

Long-term planning of municipal solid waste management systems (LPMSWMS) is a multi-layered problem that seeks answers to different decisions (i.e., method selection for the collection, transfer, treatment, and disposal of wastes, technology selection for the methods, capacity selection for the technologies, location selection for the processes, and allocation of the waste masses between locations). Since each of these decision layers has a dynamic impact on the others, all decision layers must be evaluated simultaneously in order to achieve the most accurate and effective results for the LPMSWMS. On the other hand, it is difficult to develop a mathematical model that can evaluate all decision layers simultaneously due to the complexity of the problem. Hence, almost all existing cost optimization models proposed for the LPMSWMS use a multi-step approach for the decision layers that restricts the mass balance of the waste by assuming all layers are independent from each other. However, such approaches may lead to giving up on the global optimality for the models. In this context, this study introduces a new mixed-integer nonlinear programming model for the LPMSWMS that provides an integrated mass balance for the waste streams. Regarding the current technological condition of municipal solid waste management systems, the proposed model provides integrated decisions for the LPMSWMS considering the location, technology, capacity, and waste flow plans. The proposed optimization model was tested at various spatial and temporal scales for the Bursa province of Türkiye. The optimal results obtained for the model clearly show that this new model may be the first nonlinear mathematical model capable of overcoming the above-mentioned mathematical challanges. This new model has the potential to be easily used for any region of the world and to give decision-makers the most appropriate system option for all decision layers simultaneously, as long as the site-specific waste management parameters required by the model are correctly configured. [ABSTRACT FROM AUTHOR]

Landfills are a known source of PFAS pollution. Many have environmental permits allowing the discharge of treated leachate to controlled waters. In this article we compared leachate data for 17 PFAS from 17 different landfill sites across the UK. The results show that the landfill leachate treatment process (designed to improve water quality) is generating the banned PFAS; PFOA and PFOS. Approximately 80% of locations tested showed an increase in PFOS, with an increase of 1,335% in one sample. The highest concentrations of PFOS and PFOA in treated leachate were 2,460 ng L−1 and 26,900 ng L−1, respectively. When compared against the environmental quality standard of 0.65 ng L−1 for PFOS this leachate could pose a significant concern. Landfill leachate treatment has proven effective for a wide range of different pollutants, but this research shows in several instances that it is not appropriate for PFAS remediation. [ABSTRACT FROM AUTHOR]

Introduction: In the context of rural revitalization strategies, effectively managing rural waste is a critical task for achieving ecological environmental sustainability. The current state of garbage collection and transportation is examined in this paper, focusing on the rural waste management practices in Dongfeng County, Liaoyuan City, Jilin Province, through mathematical modeling. Methods: By analyzing the rural domestic waste collection network, the volume of waste generated at various points is fuzzified using the fuzzy mathematical theory. Results: The results of path optimization for waste collection and transportation were derived from a case study, demonstrating the feasibility and practicality of the rural domestic waste recycling network model. Dicussion: Additionally, sensitivity analysis was conducted to assess the impact of changes on the total cost. Potential solutions for rural waste recycling and treatment are offered in this paper, providing valuable insights for the development of a rural domestic waste recycling network in Jilin Province. [ABSTRACT FROM AUTHOR]

The meat processing industry is rapidly growing, aiming to enhance the accessibility and affordability of meat products. However, this vital sector also presents significant environmental and social challenges alongside substantial waste management issues. Efforts to improve sustainability in this industry include introducing advanced waste treatment technologies. This study evaluates the overall sustainability of the meat processing industry by comparing the current waste treatment system with an advanced system incorporating improved technologies for water reuse, solid waste valorization, and energy production. We conducted environmental, social, and economic Life Cycle Assessments (LCAs) using OpenLCA and the SOCA v2 database, with 1 kg of processed meat as the functional unit. The comparative analysis highlights significant improvements in the '50%' scenario, where half of the wastewater undergoes advanced treatment. Environmental impacts decreased notably: Freshwater Eutrophication and Human Carcinogenic Toxicity by 25.9% and 31.5%, respectively, and Global Warming and Fossil Resource Scarcity S by 9.2% and 8.8%. Social risk indicators improved by 33.7% to 37.0%. The treatment system achieved a cost saving of EUR 0.00187 per kg of meat (EUR 63,152.70 annually), though these results are specific to this study and heavily dependent on the location and time period. Further analysis of four scenarios, including the baseline, demonstrated that increasing the proportion of wastewater treated by the new system improved environmental, social, and economic outcomes, with the 75% treatment scenario proving the most sustainable. Overall, the advanced treatment system significantly enhances sustainability in the meat industry, promoting a more environmentally, socially, and economically friendly waste management approach. [ABSTRACT FROM AUTHOR]

The processing of paper sludge is currently an important environmental topic due to its high global production. The aim of this study is to monitor the biodegradation of paper sludge when the initial conditions change. Biodegradability tests 301F and OECD 311 were used to determine biodegradation. The data obtained from the tests were subsequently obtained for the simulation in MATLAB R2023b. The highest aerobic decomposition was approximately 80% after 28 days at an initial concentration of paper sludge leachate of 76 g/L. By simulating 3D modelling, we can predict that with a retention time of 1 day with degradation under aerobic conditions at the level of 70%, the ideal initial concentration of organic substances will be 157.55 g/L. Based on this model, it is possible to estimate that with a biogas production of 554 m3/tVS and a decomposition time of 20 days, it is necessary to set a concentration of approximately 128 g/L. Based on biodegradability tests, paper sludge was evaluated as suitable for aerobic or anaerobic biological decomposition. [ABSTRACT FROM AUTHOR]

Cu‐exchanged chabazite zeolite is the state‐of‐the‐art used on‐board catalyst for NOx selective reduction by ammonium (NH3‐SCR), and the zeolite is currently generated in the presence of N,N,N‐trimethyl‐1‐adamantylammonium hydroxide, serving as organic structure‐directing agent (OSDA). The expensiveness of this OSDA increases the catalyst production cost, while its low degradability brings about environmental concerns in post treatment of waste water. Here, a new type OSDA, 1‐(1‐methylpropyl)‐4‐aza‐1‐azoniabicyclo[2.2.2]octane hydroxide, is proposed to direct Faujasite‐to‐Chabazite inter‐zeolite conversion and generate chabazite with Si/Al ratio up to 7.2. The obtained zeolite possesses high hydrothermal stability for the high crystallinity, siliceous framework and low concentrations of Si(2Si, 2Al) sites. The Cu‐form catalyst exhibits better catalytic performance in standard NH3‐SCR process for the tiny crystallite size (35–258 nm) and formation of highly dispersed copper sites. The synthesis offers a new type of OSDA to fabricate zeolites and expands the toolkit to regulate their physicochemical properties. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The extraction of mining resources, as well as processing processes such as ore beneficiation and smelting, generate large amounts of tailings that are difficult to directly utilize. Meanwhile, substantial filling materials are required for the voids formed after mining operations, and the environmental issues and safety hazards brought on by massive solid waste disposal cannot be ignored. By utilizing solid waste with alkaline and pozzolanic activity as the binder component and gold tailings as filler aggregate to prepare filler material to fill up the void areas, the purpose of waste treatment can be achieved. In this study, salt sludge, steel slag, ground granulated blast furnace slag, and gold tailings were used to prepare all-solid waste fluidized filling material for filling mine void areas, which not only solves the engineering safety problem of easy collapse of the mine airspace in the mining process but also ensures a backfill effect with high strength, which continuously guarantees the uninterrupted progress of the mining project. At the same time, the preparation of fluidized materials can consume a large amount of tailings and other solid waste, solving the problem of their stockpiling. The components of the solid wastes used are all general industrial solid wastes, so the preparation of the fluidized materials will not have an impact on the surrounding environment. The effects of binder ratios on the workability of the filling materials were investigated by means of the slump and slump flow tests. Combined with the unconfined compressive strength test, the change in backfill material strength with curing age and the water–binder ratio was studied. The experimental results showed that the slump and slump flow value of the filling material were positively correlated with the water–binder ratio. The water–binder ratio range satisfying a slump value of 180~260 mm and a slump flow value not less than 400 mm was 0.95~1.106. However, the strength decreased with the increase in the water–binder ratio, conforming to a hyperbolic relationship. The all-solid waste fluidized filling material had strengths not less than 0.22, 1.09, and 1.95 MPa at 3, 7, and 28 d, respectively, meeting the workability requirements. Finally, a method for determining the optimal range of water–binder ratio considering both workability performance and strength is proposed based on the relationship between slump value, slump flow value, unconfined compressive strength, and the water–binder ratio. [ABSTRACT FROM AUTHOR]

Aquaculture stakeholders have mental models, which are the internal cognitive representations of how they understand and prioritize the different features of their aquaculture systems. Individuals and stakeholder groups are likely to have different mental models, with implications for making cooperative governance work and guiding the rapidly emerging sector's sustainable development. We apply a participatory approach called fuzzy cognitive mapping to capture and compare the mental models of community-based coastal pond aquaculture stakeholders in Indonesia, including farmers, government managers, and researchers who need to work together to govern a rapidly expanding aquaculture sector which faces critical sustainability challenges. To conceptually structure our comparison, we use Elinor Ostrom's social–ecological systems framework. Our results highlight important differences between stakeholder group mental models which represent potential conflicts of interest and barriers for collaborative governance. Fish farmer models emphasize resource system challenges relating to production instability and risk, while government managers emphasize increasing production intensity to meet sectoral growth targets. Researchers, in contrast, tend to focus on pond waste treatment and water quality management. Governance attributes were consistently perceived as less frequent and less influential compared to other social–ecological dimensions, reflecting perceptions of weak governance in the sector. We identify a critical need for programs aimed at strengthening community-level institutional arrangements for governing shared aquaculture resources, increasing technical knowledge capacity, and managing financial risk. By merging all stakeholder models into a single "community" model, we identify key consensus action situations across the three groups as potential focal points for aquaculture development which may serve as a starting point for actors to work together to identify context-appropriate institutional solutions to these sustainability challenges. [ABSTRACT FROM AUTHOR]

Today, dental tourism is regarded as one of the most important tourist industries due to its high demand and financial transactions. Sustainable development has become increasingly important because of the depletion of natural resources, health problems, and waste management. Contrary to the previous works, we firstly develop a multi-objective mathematical model seeking to reach and optimize sustainable objectives in the dental tourism supply chain. To achieve these aims, optimal locations of dental clinics and accommodation facilities and their required number and capacities are found. Besides, transportation activities and waste treatment facilities are optimized based on supply and demand. Biological risks, job vacancies creation, environmental issues, and costs and profits are considered in our work. Also, an improved goal programming is employed to solve the model. In addition, this model is implemented and analyzed by a real case study of the dental tourist industry to validate the proposed model. The government and practitioners of private sectors would derive great benefits from the real case outputs to build a thriving business from sustainable perspectives. [ABSTRACT FROM AUTHOR]

Biological waste treatment technology is currently the world's largest application process, and its functional achievement mainly relies on complex microbial communities. However, the microbial system in such engineered ecosystems has been considered a "black box." Over the past decade, with the development of molecular biotechnology and next-generation sequencing technologies, the exploration of such "black boxes" has gradually deepened. In particular, the role of ecological forces in uncovering and regulating microbial communities has been largely recognized and has provided novel insights into the link between microbial communities and engineering objectives. However, the study of community ecology in engineered ecosystems is still in its early infancy and faces grand challenges in bridging engineering principles with microbial ecology theory. In this review, we discuss recent advances in the understanding of microbial community behavior in biological waste treatment systems, including biodiversity and its influencing factors, the role of neglected rare species, microbial interactions, and community assembly mechanisms. We emphasize the importance of these ecological perspectives in revealing and regulating microbial communities and functions, such as the enhancement of contaminant removal and operational stability in engineered ecosystems. In particular, cross-validation of the microbial community analysis results is necessary to yield valid real information to guide the improvement and stability of engineering ecosystem performance. Multi-omics approaches and synthetic community biology are preferred ways to link ecological theory and engineering objectives. [ABSTRACT FROM AUTHOR]

Illegal or unwanted waste disposal methods such as dumping and export are prevalent in practice. To minimize the environmental harm of these methods, policymakers have implemented laws and regulations designed to combat them. Even so, violations are rampant as a high degree of heterogeneity between firms and proprietary information render monitoring imperfect. Decentralized waste disposal chains, a common form of interbusiness organization in this sector, compound this problem as firms also have limited information available on their waste chain partner, creating complex interactions between firm behavior and policy interventions. Against this background, we analyze the effects of domestic and international waste regulations targeting dumping and export, respectively, on firm incentives and compliance. We develop a two-tier waste chain with a producer that generates waste and an operator that treats it. The producer's waste quality and the treatment operator's efficiency can be private information. Either party can avoid compliance cost by violating regulations where the producer can arrange for export and the operator can dump locally. Our analysis reveals that primarily focusing on penalizing dumping by treatment operators can worsen environmental harm. Solely focusing on penalizing low-quality waste exports, a common intervention in practice, can also backfire. Instead, penalizing producers for downstream dumping should be given consideration. In addition, the asymmetry in export burden between waste quality levels should be reduced. This paper was accepted by Vishal Gaur, operations management. [ABSTRACT FROM AUTHOR]

Ananas comosus leaves were converted to a porous graphitized carbon (GPLC) material via a high-temperature pyrolysis method by employing iron salt as a catalyst. A cobalt molybdate (CoMoO4)-and-GPLC composite (CoMoO4/GPLC) was then prepared by engineering CoMoO4 nanorods in situ, grown on GPLC. N2 adsorption–desorption isothermal curves and a pore size distribution curve verify that the proposed composite possesses a porous structure and a large specific surface area, which are favorable for charge and reactant transport and the rapid escape of O2 bubbles. Consequently, the as-synthesized CoMoO4/GPLC shows low overpotentials of 289 mV and 399 mV to afford the current densities of 10 mA cm−2 and 100 mA cm−2 towards the oxygen evolution reaction (OER), which is superior to many CoMoO4-based catalysts in previous studies. In addition, the decrease in current density is particularly small, with a reduction rate of 3.2% after a continuous OER procedure for 30 h, indicating its good stability. The excellent performance of the CoMoO4/GPLC composite proves that the GPLC carrier can obviously impel the catalytic activity of CoMoO4 by improving electrical conductivity, enhancing mass transport and exposing more active sites of the composite. This work provides an effective strategy for the efficient conversion of waste ananas comosus leaves to a biomass-derived-carbon-supported Co-Mo-based OER electrocatalyst with good performance, which may represent a potential approach to the development of new catalysts for OER, as well as the treatment of waste biomass. [ABSTRACT FROM AUTHOR]

Selective uptake and elution of trace amounts of hazardous radioactive 90Sr from large-scale high-level liquid waste (HLW) is crucial for sustainable development. Here, we propose a site differentiation strategy, based on the presence of distinct selective metal capture sites (concavity site and tweezer site) within the giant polyoxoniobate (PONb) nanoclusters of an all-inorganic PONb framework (FZU-1). Through this strategy, FZU-1 can not only effectively remove 98.9% of Sr²⁺ from simulated nuclear liquid waste, performing best among the reported Sr adsorbents, but also achieve desorption of adsorbed Sr²⁺ ions by selectively loading Na⁺ ions, thus enabling the recycling of FZU-1. Based on the well-defined single-crystal structures and theoretical studies, it can be revealed that the rapid and selective uptake of Sr²⁺ is attributed to the strong binding energy between the Sr²⁺ ions and the concavity sites. The effective elution of Sr²⁺, on the other hand, stems from the preferential binding of Na⁺ ions at the tweezer sites, elevating the cluster's electrostatic potential and indirectly facilitating the elution of Sr²⁺ ions. The exceptional stability of FZU-1, along with its rapid and selective Sr²⁺ capture and elution capabilities, positions it as a promising candidate for large-scale nuclear waste treatment and groundwater remediation applications. Here, the authors propose a site differentiation strategy in ion exchange, that is, functional materials with different adsorption sites for specific metal ions can achieve efficient uptake and elution of specific ions (e.g., Sr2+ ion in this work). [ABSTRACT FROM AUTHOR]

Cobalt (Co) is a hazardous element of significant environmental concern, primarily due to its potential leaching toxicity. However, the current assessments of leached Co residues have focused solely on the total cobalt concentration, often overlooking the distinct Co species that contribute to its hazardous nature. This study attempts to determine the impact of cobalt speciation on the toxicity of cobalt and the related hazardous characteristics. The objective of this study is to enhance the understanding of how different Co species influence the environmental toxicity of leached residues. Cobalt speciation is studied by a multivariate analysis including ignitability, reactivity, corrosiveness, acute toxicity, leaching toxicity, and toxic substance concentration. The tested concentrations are compared with the identification standards and technical specifications in China. Co species, particularly cobalt oxide, are identified as the main contributors to the toxicity of the leached Co residue. It is also noted that Co occurrence significantly affects the calculation results of cumulative toxicity, thus impacting the hazard characteristics of leached cobalt residue. The findings benefit risk evaluators and decision makers by offering a new approach for managing leached Co residues and providing a scientific foundation for the development of relevant laws and regulations in China. [ABSTRACT FROM AUTHOR]

The World Health Organization recommends using weight-for-height Z-score (WHZ) <-3 or Mid-Upper Arm Circumference (MUAC) <115 mm as independent criteria for diagnosing severe wasting. However, there are several challenges in using the WHZ criterion. As a result, the MUAC (and edema)-only approach for identifying children needing treatment for severe wasting has been developed and is being rapidly scaled-up globally, including in Timor-Leste. But previous studies reported that MUAC<115 mm has poor diagnostic accuracy for detecting children with WHZ<-3. The two options being explored globally for improving the identification of these children in MUAC (and edema)-only programming contexts include expanding MUAC cut-off and the combination of the indicators MUAC and Weight-for-Age Z-score (WAZ). This study explored the accuracy for diagnosing severe wasting (WHZ<-3) of these two options in Timor-Leste. We conducted a secondary analysis of data from the 2020 national Timor-Leste Food and Nutrition Survey. We tested the accuracy of various MUAC cut-offs, and predefined case definitions in five age groups (0–5 months, 6–23 months, 24–59 months, 6–59 months, and 0–59 months). We calculated the standard diagnostic test parameters (sensitivity, specificity, Youden Index, and others) and used the Youden Index as the principal criterion for rating the overall level of accuracy. The sample analyzed comprised 11,056 children with complete information on our key variables (anthropometric data, age, and sex), of whom 52.2% were boys. The age groups 0 to 5 months, 6 to 23 months, and 24 to 59 months represented 9.0%, 33.7%, and 57.3% of the sample, respectively. We found that the optimal diagnostic MUAC cut-off varied across the age groups between 117 mm and 142 mm, with the Youden Index remaining < 55% in all the age groups considered. The use of case definitions combing MUAC and WAZ optimized the identification of children with WHZ<-3. The case definition MUAC<130 mm or WAZ<-3 Z-score had the best diagnostic accuracy in all the age groups except for the 0 to 5 months age group for which the case definition MUAC<110 mm or WAZ<-2 Z-score had the highest Youden Index. Our findings show that it is challenging to significantly improve diagnostic accuracy for identifying children with WHZ<-3 by only expanding the MUAC cut-off in under five Timorese children. However, In settings facing challenges in using WHZ, the combination of MUAC and WAZ indicators offers a promising approach. Further research is needed to confirm the effectiveness of the proposed combination of MUAC and WAZ indicators case definitions in a programmatic context in Timor-Leste, and other similar contexts. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) use the metabolic actions of microorganisms in an anode chamber to convert the chemical energy from wastewater into electrical energy. To improve the MFC power generation performance and chemical oxygen demand (COD) removal efficiency, Stenotrophomonas acidaminiphila was added to the anode chamber of a dual-compartment MFC. In this process, Stenotrophomonas acidaminiphila promotes the degradation of macromolecules such as bis(2-ethylhexyl) phthalate in food waste oil. Additionally, the generated electrical energy reduced Cu2+ in the copper-containing wastewater in the cathode chamber to Cu monomers. The maximum power density of the MFC was 49.5 ± 3.5 mW/m2, the maximum removal efficiencies of COD and Cu2+ were 63.5 ± 5.8% and 96.5 ± 1.0%, respectively, and Cu2+ was reduced to brick-red Cu monomers. This study provides insights into the simultaneous implementation of food waste oil treatment and metal resource recovery. [ABSTRACT FROM AUTHOR]

Waste sulphur produced in industrial processes is often exposed to the air, and its diffusion and combustion in the environment can produce harmful substances, posing a significant risk to ecological safety and human health. Herein, a novel method for the direct treatment of solid sulphur with manganese dioxide based on a simple sealed reactor is proposed. Significantly, the developed sulphur treatment technology could prepare high purity manganese sulphate at the same time. Under the optimum conditions of the reaction temperature of 187.2°C, reaction time of 21.6 h, sulphuric acid loading of 1.00 mol ∙ L−1, and manganese dioxide dosage of 4.00 mol ∙ mol‐S−1 derived by the response surface method (RSM), the removal efficiency of sulphur could reach near 100%, and the purity of the manganese sulphate product obtained was more than 98%. Kinetic model fitting analysis and several characterization methods were adopted to confirm that the reaction process between sulphur and manganese dioxide follows the unreacted nuclear model controlled by surface chemical reaction, and the transformation paths of Mn and S elements were proposed. This study provides a novel method for the resource treatment of waste sulphur and the preparation of high purity manganese sulphate. [ABSTRACT FROM AUTHOR]

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

Solid waste treatment is an acute concern for countries facing waning landfilling capacity, increasingly strict controls on waste transport and treatment, and the persistent threat of climate change. These challenges are typically met by neoliberal and technocratic solutions that privatize public services while encouraging curbside recycling. I examine such an effort to promote curbside recycling in Israel. Drawing on extensive fieldwork in the Israeli recycling world, and on anthropology, geography, science and technology studies and critical waste studies literatures, I interrogate the affective politics of household waste recycling in Israel over the past decade and attempts to configure a Europeanized and moral national space through recycling. I describe the cultural and ethnonational repertoires through which curbside recycling was naturalized in the Israeli landscape, how recycling was mutually animated with a range of sociopolitical concerns that far exceeded its financial or environmental significance, and how these mutually shaped waste as a social–environmental problem. I argue that social and material conditions gave rise to a dual process, in which both the problem of waste, and its necessary solutions, were actively and mutually constructed. This paper contributes to comparative literatures on national cultures of waste recycling, shedding light on how a project of Western ecological modernization was translated and became locally meaningful in Israel's settler-colonial context, how household waste was ontologically coproduced in this process, and how its stakes were experienced, voiced, and materialized. [ABSTRACT FROM AUTHOR]

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

Genes conferring antibiotic resistance phenotype, particularly to last resort antibiotics, pose a significant concern globally. Wastewater treatment plant (WWTP) effluent substantially contributes to antibiotic resistance in receiving rivers, threatening human health. Globally, colistin- and carbapenem-resistant Klebsiella pneumoniae infections cause high morbidity and mortality. We investigated colistin-resistant carbapenemase-producing K. pneumoniae (Co-CRKP) isolates in Kathajodi river receiving WWTP effluent, their resistance genes, and pathogenic potential. Four isolates (Co-CRKP-7, Co-CRKP-8, Co-CRKP-10, and Co-CRKP-15) exhibited extensively drug-resistant (XDR) phenotype, harbouring bla TEM-1, bla CTX-M-15, bla NDM-5, and bla OXA-48 genes. Colistin resistance was attributed to mutations in the pmrA and pmrB genes. Virulence genes (fimH, mrkD, entB, iucA, iutA , and irp1), capsular serotypes (K1, K2) and biofilm formation in the isolates explicated their pathogenicity. Furthermore, Inc plasmid replicons (Y, FrepB, P, K/B, L/M, N, FIA, A/C, and FIB) indicated the dissemination potential of the resistance genes in Co-CRKP isolates. The multi-locus sequence typing showed that Co-CRKP-7 and Co-CRKP-8 belonged to ST42, while Co-CRKP-10 and Co-CRKP-15 were ST16 and ST231, respectively. These high-risk clones carrying multidrug resistance and virulence genes, implicated in numerous outbreaks, have spread worldwide. Our findings emphasize the necessity for effective treatment of hospital wastes to restrict the spread of clinical isolates into aquatic environments. [ABSTRACT FROM AUTHOR]

Copyright of Applied Chemical Industry is the property of Shaanxi Research Design Insitute of Petroleum & Chemical Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Current research aims to improve the characteristics of lithium manganese oxide (LiMn2O4), a highly prospective for waste water treatment applications, by incorporating gadolinium (Gd-0.25 %) into the manganese position. This integration, achieved via conventional ball milling, aims to improve the structural, morphological, and electrical characteristics of Li4Mn5O12. A range of analytical methods, such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and impedance testing, were utilized to evaluate the influence of Gd-0.25 % on Li4Mn5O12. The results indicate that the inclusion of Gd at the manganese sites enhances the thermal conductivity of Li4Mn5O12 (Li4Mn4.75Gd0.25O12), leading to improved conductivity compared to undoped Li4Mn5O12. Additionally, the enhanced material exhibits promising potential as an efficient photocatalyst, demonstrated by its degradation of methylene blue (MB) dye. [ABSTRACT FROM AUTHOR]

The spent alum sludge was employed for the removal of specific fission products including 137Cs, 85Sr, 152+154Eu, 99Mo, and 99Tc radionuclides from radioactive waste. The physicochemical features of spent alum sludge were investigated. The results illustrated that the uptake percentages were 94.2, 90.5, 87.6, 87.1, and 76.6%, correspondingly, for 99Mo, 152+154Eu, 99Tc, 85Sr, and 137Cs. The kinetic studies illustrated that the adsorption process obeyed Langmuir kinetics which is a combination of first-order and second-order expressions. The findings demonstrated that the spent alum sludge can be applied successfully as a low-cost and effective adsorbent for the treatment of radioactive waste. [ABSTRACT FROM AUTHOR]

Waste management involves the systematic collection, transportation, processing, and treatment of waste materials generated by human activities. It entails a variety of strategies and technologies to diminish environmental impacts, protect public health, and conserve resources. Consequently, providing an effective and comprehensive optimization approach plays a critical role in minimizing waste generation, maximizing recycling and reuse, and safely disposing of waste. This work develops a novel Possibilistic Multi-Objective Mixed-Integer Linear Programming (PMOMILP) model in order to formulate the problem and design a circular–sustainable–reliable waste management network, under uncertainty. The possibility of recycling and recovery are considered across incineration and disposal processes to address the main circular-economy principles. The objectives are to address sustainable development throughout minimizing the total cost, minimizing the environmental impact, and maximizing the reliability of the Waste Management System (WMS). The Lp-metric technique is then implemented into the model to tackle the multi-objectiveness. Several benchmarks are adapted from the literature in order to validate the efficacy of the proposed methodology, and are treated by CPLEX solver/GAMS software in less than 174.70 s, on average. Moreover, a set of sensitivity analyses is performed to appraise different scenarios and explore utilitarian managerial implications and decision aids. It is demonstrated that the configured WMS network is highly sensitive to the specific time period wherein the WMS does not fail. [ABSTRACT FROM AUTHOR]

Reuse of wastewater is a promising response to water scarcity. For peri-urban areas served by decentralized wastewater treatment plants, the delivery of treated wastewater to the households may be a viable option to promote reuse on a larger scale. Based on a case study in Eastern India, this paper explores if households would accept recycled water for non-potable purposes and if they would pay for it. While the respondents to household surveys had very positive views about recycling, they were not willing to pay much, even if they were from a middle-income class and could afford more. A closer analysis of the attitudes towards recycling indicated knowledge gaps about the risks and advantages of using recycled water. [ABSTRACT FROM AUTHOR]

The potential effects of combining biochar with hyperaccumulator plants on heavy metal stabilization and uptake in Cd and Pb-contaminated soils have received limited attention. This study used biochar (BC) at levels ranging from 0 to 40 t ha-1 as soil amendments in Cd and Pb contaminated rice paddy soil. Biochar significantly decreased soil bioavailable Cd and Pb concentrations 6.7 to 16.6% and 10.6 to 39.7%, respectively, compared to the control. The shoot and root Cd concentrations in Arabidopsis helleri increased significantly by 33.5% and 133.1%, respectively, in the C3 treatment compared to the control. Similarly, shoot Pb concentrations showed a 57.5% increase compared to the control, but no significant changes were observed in root Pb concentrations. The Arabidopsis helleri bioconcentration factor (BCF) saw an increase of up to 40.5% for Cd and 57.8% for Pb with the C3 treatment. Conversely, the Cd translocation factor (TF) decreased 42.8 to 49.1%, while the Pb TF increased 32.8 to 96.6% with biochar application. The majority of Arabidopsis helleri-biochar Cd and Pb was found in the B3 fraction (organic fraction), constituting over 50%, and even over 80% for Cd. The Arabidopsis helleri-biochar primarily contained organic char binding Cd and exhibited slow-release characteristics. [ABSTRACT FROM AUTHOR]

Onion skin constitutes a major part of industrial food waste, and cold plasma technology can be employed in the treatment of onion skin. Onion skin waste was ground and exposed to dielectric barrier discharge cold plasma (DBDCP) at 40 kV for 10 or 20 min. Samples that were not DBDCP treated were used as the control. The changes in the color, microbial load, total phenolic content (TPC), and antioxidant activity of the onion skin waste upon treatment were evaluated. An increase in the b* and C* values of the onion skin powder (OSP) was obtained after the DBDCP treatment. The DBDCP process also decreased the total mesophilic aerobic bacteria and yeast–mold counts of the OSP by up to 0.92 and 0.97 log cfu/g (colony‐forming units per gram), respectively. In addition, the TPC and antioxidant activity, as determined by 2,2‐diphenyl‐2‐picrylhydrazyl (DPPH) scavenging activity and ferric‐reducing antioxidant power (FRAP) methods, were increased for up to 59% and 28%, respectively, depending on the treatment time. In conclusion, the findings of the study show that using DBDCP processing in the treatment of onion skin waste can reduce microbial count while enhancing TPC and antioxidant activity. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) is crucial for carbon cycle, residents' lives, and green circular economy development, but quantitative research is limited in efficiency and regional synergy. Considering the regional characteristics of Chengdu and Chongqing, this study establishes the input–output indicator system of MSW treatment in 16 cities in the Chengdu–Chongqing area, constructs the Data Envelopment Analysis model and the coupling coordination degree model, and makes an in‐depth study on the efficiency and environmental benefits of MSW resource treatment from 2012 to 2021. The research conclusion is as follows: first, the improvement of MSW treatment efficiency can be enhanced through reasonable policies and measures to promote sustainable urban development and socioeconomic benefits. The input and output levels of MSW treatment in 16 cities all show an upward trend. Second, the 16 MSW treatment systems have good average pure technical efficiency (Chongqing 0.9879, Chengdu 0.9805), average scale efficiency (Nanchong 0.9396), and average comprehensive efficiency (Nanchong 0.9148), but the overall comprehensive efficiency needs improvement. Third, in 2021, Chengdu's ecological and environmental benefits are better than Chongqing's, while Chongqing has a certain degree of input redundancy and output deficiency. Fourth, in the coupling analysis of resource treatment efficiency and environmental improvement benefits in Chengdu and Chongqing between 2012 and 2021, the coordination between resource treatment and environmental improvement in Chengdu lags behind that in Chongqing, but overall, the coupling is improving. Finally, suggestions for improving the efficiency of MSW resource treatment and promoting environmental improvement are presented from the front, middle, and back ends, respectively, to provide a reference for the policy‐making of city managers. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global waste management challenges demand innovative and multi-functional solutions. The Nordic Biogas Model (NBM) based on anaerobic digestion of organic waste and valorization of its outputs provides several benefits beyond waste treatment such as energy recovery, nutrient recycling and climate impact mitigation. Despite these benefits, its international adoption remains limited, revealing an implementation gap. One way to address this gap is to adapt technology and knowledge from the provider to each specific context. This involves the embedding of the technology into the local context and the development of conditions such as formal and informal institutions over time. Based on decade-long interactions with Nordic companies and municipal decision-makers, we highlight the importance of communication between the technology provider and potential adopter, to ensure that the diverse sustainability benefits of NBM are acknowledged. Furthermore, most provider companies can benefit from a systematic guideline that supports early-stage decision-making as an essential component of the adaptation and implementation of the NBM in diverse international contexts. In this article, we offer suggestions for both: (1) how to better communicate the sustainability benefits of the NBM, and (2) how to assess the risk and opportunities of entering new markets at the early stages of decision-making. [ABSTRACT FROM AUTHOR]

Alkaline proteases derived from haloalkaliphiles, extremophilic microorganisms thriving in high-pH and high-salt environments, have garnered significant attention in recent years due to their unique biochemical properties and versatile applications. This review highlights the isolation, characterization, and biotechnological potential of alkaline proteases produced by haloalkaliphilic microorganisms. Haloalkaliphiles, found in soda lakes, saline-sodic soils, and other extreme habitats, have evolved to adapt and thrive under conditions characterized by elevated alkalinity and salinity. Alkaline proteases from these microorganisms exhibit high stability and activity under extreme pH and salinity, making them valuable candidates for various industrial processes. The review provides insights into the biochemical properties of alkaline proteases, including optimal pH, temperature, stability, and substrate specificity. Molecular studies have revealed unique structural features that contribute to the stability of these enzymes under harsh conditions, shedding light on their potential applications in challenging industrial processes. The industrial applications of alkaline proteases from haloalkaliphiles are diverse and encompass several sectors. Their role as powerful biocatalysts in detergent formulations is well-established, where they effectively break down proteinaceous stains under high pH conditions. Additionally, these enzymes find applications in leather processing, food industry, waste treatment, and pharmaceuticals, owing to their ability to operate efficiently in alkaline and saline environments. Their stability under extreme conditions, coupled with advances in biotechnological approaches, positions these enzymes as crucial components in the development of sustainable and efficient processes across various industries. Continued research in this field holds promise for discovering novel enzymes and unlocking their full potential for biotechnological innovation. [ABSTRACT FROM AUTHOR]

The coagulation and flocculation properties of chitosan, an organic biopolymer derived from chitin, have been researched as an alternative to synthetic polymers and inorganic metal salt coagulants currently used in water and wastewater treatment. In an effort to encourage further research into the practical uses of chitosan as green chemistry in water and wastewater treatment and to promote the efficacious removal of microbial contaminants in drinking and wastewater, we have summarized the current state of research pertaining to the treatment of microorganisms in water and wastewater. A search of PubMed revealed 720 possible titles and abstracts, of which 44 full-text articles were identified as matching the eligibility criteria for inclusion in this systematic review. Results are presented based on the type of water matrix treated (i.e., drinking water, wastewater, and recreational waters) and a summary table providing details on the types and forms of chitosan utilized and the treatment mechanisms and processes described in the study. We find chitosan to be an effective coagulant, flocculant, and adsorbent for removing microbes from water and wastewater; some modified forms of chitosan can inactivate microbes and achieve disinfection, such as those containing metals like silver and antimicrobial chemicals like quaternary ammonium compounds or other strong oxidants, and use with filtration or electrochemical processes can achieve extensive reductions in microbes to meet performance targets of the World Health Organization. [ABSTRACT FROM AUTHOR]

Textile waste is becoming among the most polluting waste in the world, discarded mostly in landfills. Valorizing textile waste via anaerobic digestion (AD) helps conserve resources, reduce environmental impact, and foster a circular economy. Although several reviews have discussed textile waste AD, there is a lack of detailed understanding of the challenges encountered during textile waste AD. Therefore, the goal of this review is to focus on challenges encountered and possible solutions for those challenges for biogas and fertilizer conversion via AD. Potential strategies include chemical, biological, and thermal pretreatments that significantly increase the digestion process. Co‐digestion of natural textile waste, cotton, and wool with carbon and nitrogen‐rich substrates improves AD efficiency by twofold. Moreover, separating polyester from polycotton and textile dye removal via solvent and advanced oxidation processes significantly increases methane yield compared with untreated textile waste. This review can aid in analyzing suitable methods to optimize the biogas production of textile waste via AD. [ABSTRACT FROM AUTHOR]

The contamination of water bodies is becoming more frequent due to uncontrolled discharges into them, including those of domestic or industrial wastewater (WW) characterized by the presence of heavy metals, a high pathogenic load, pesticides, and pharmaceuticals, among other pollutants, which represent a risk to both humans and the health of the ecosystem. Consequently, conventional water treatment processes have been implemented. However, they are not efficient enough. In this regard, exploring and analyzing new alternatives and sustainable systems that efficiently degrade the different pollutants found in WW are required, and biochar can be considered as an attractive treatment option, since it is an adsorbent carbonaceous material that allows for the removal of several pollutants. The generation and use of biochar contribute to the promotion of the circular bioeconomy and the achievement of sustainable development goals by enhancing the reuse and recycling of agricultural and agro-industrial waste as raw material for its production. The objective of this work is to evaluate the utilization of biochar as an alternative material for the elimination of the pathogenic load in water. [ABSTRACT FROM AUTHOR]

This study explores sustainable methods for Sardine Processing Waste (SPW) valorization. Two approaches were investigated: (a) SPW microbial pretreatment adding Saccharomyces cerevisiae or Bacillus sp. in a two-stage anaerobic digestion (AD) for enzyme and biomethane production and (b) a single-stage AD without SPW pretreatment. Both S. cerevisiae and Bacillus sp. secreted proteases (0.66 and 0.58 U mL−1, respectively) and lipases (3.8 and 4.3 U mL−1, respectively) during hydrolysis, thus reducing viscosity (2.8 and 2.9 cP, respectively) compared with the untreated SPW (4.1 cP). Biomethane production was higher in the single-stage AD (1174 mL CH4 g−1 VS−1) when compared with the two-stage AD (821.5 and 260 mL CH4 g−1 VS−1 with S. cerevisiae and Bacillus sp., respectively). S. cerevisiae addition enhanced SPW degradation as implied by VS and sCOD values (70 and 84%, respectively), but this also resulted in a higher toxicity due to a three-fold increment in NH4-N content, reducing methanogen activity. This research demonstrates the innovative application of S. cerevisiae, a common bread-making yeast, in the biotechnological enhancement of SPW hydrolysis. Non-genetically engineered S. cerevisiae not only co-produced proteases and lipases but also significantly improved solubilization, degradation, and viscosity reduction, thereby rendering the yeast a key player in solid fish waste valorization, beyond its traditional applications. [ABSTRACT FROM AUTHOR]

Municipal waste water treatment plants have a fundamental task, which is to rid waste water of toxic and health-threatening organic and inorganic substances, including unwanted microorganisms and other pollutants, with the highest possible efficiency so that the discharged water does not contaminate the natural environment, which happens in the case of imperfect cleaning. Current WWTPs usually have a preliminary, primary, and secondary stage, and in very few cases even a tertiary stage, which no longer guarantees the sufficient removal of pollutants from waste water. This research presents the current situation in different parts of the world concerning the possibility of solving the current situation regarding the tertiary and quaternary stages of this process, especially in small and rural WWTPs serving up to approx. 10,000 equivalent inhabitants, which could ensure the removal of so-called emerging pollutants, including microplastics, and would stop WWTPs being point sources of environmental contamination. [ABSTRACT FROM AUTHOR]

Featured Application: Our results demonstrate the easy and accurate control of the amount of active ingredient relative to its degradation product in waste water treatment materials containing ferrate(VI). Potassium ferrate(VI) (K2FeO4) as a particularly strong oxidant represents an effective and environmentally friendly waste water treatment material. When produced by anodic oxidation in highly alkaline aqueous solution, the K2FeO4 product is separated and sealed in inert plastic bags with the retention of some liquid phase with high pH. This method proved to be excellent for long-term storage at moderately low temperature (5 °C) for industrial applications. It is still imperative to check the ferrate(VI) content of the product whenever it is to be used. Fe-57 Mössbauer spectroscopy is an excellent tool for checking the ratio of ferrate(VI) to the degradation product iron(III) in a sample. For this purpose, normally the spectral areas of the corresponding subspectra are considered; however, this approximation neglects the possible differences in the corresponding Mössbauer–Lamb factors. In this work, we have successfully determined the Mössbauer–Lamb factors for the ferrate(VI) and for the most common iron(III) degradation products observed. We have found superparamagnetic behavior and low-temperature phase transformation for another iron(III) degradation product that made the determination of the Mössbauer–Lamb factors impossible in that case. The identities of a total of three different iron(III) degradation products have been confirmed. [ABSTRACT FROM AUTHOR]

The selection of adsorbents is critical for developing an adsorption unit. In this study, a activated carbon fibers (ACF) and a granular‐activated carbon (GAC) were evaluated in dynamic toluene adsorption to determine their benefits and limitations. A variety of physicochemical approaches were used to characterize the samples. Adsorption under varied circumstances demonstrated that ACF has a larger adsorption capacity and a longer saturation time than GAC. The Langmuir isotherm suited equilibrium data well. Thermodynamic characteristics showed that adsorption was spontaneous and exothermic. The adsorption kinetics were found to be dominated by the pseudo‐first‐order model, with GAC having a greater sorption rate. Thermal regeneration appeared to be more favorable for ACF. [ABSTRACT FROM AUTHOR]

Nano-filtered whey permeate (WP), a major by-product of dairy industry, is produced by membrane filtration of whey. The oleaginous microalga Nannochloropsis oceanica was successfully cultivated on WP without salinity and nutrient amendments. Growth, cell characteristics, and fatty acid profile of the cultures were analyzed using microscopy, flow cytometry, and GC analysis. WP was nitrogen limited, comprising primarily protein as a nitrogen source and only small amounts of free inorganic nitrogen (in the form of nitrate). Nannochloropsis oceanica (and associated bacteria) efficiently removed nitrate (100%), protein (87%), and phosphate (74%) from the whey permeate. Microscopic and flow cytometric analysis revealed diverse size distributions in whey permeate cultures, with significant cell aggregation attributed to low-salinity acclimatization and nitrogen limitation. Autofluorescence analysis revealed reduced photosynthetic activity in whey permeate-grown cells, possibly as a consequence of heightened mixotrophic activities on carbon source in the medium. Low nitrogen availability in whey permeate resulted in biomass with a fatty acid profile enriched in saturated fatty acids. Despite this, a considerable level of the omega-3 polyunsaturated fatty acid (in the form of eicosapentanoic acid or EPA) was detected at ca. 16% of total fatty acids. Whey permeate proved beneficial for the growth of N. oceanica and yielded high concentrations of eicosapentaenoic acid in the extracted lipids for potential applications in the feed/food industries. [ABSTRACT FROM AUTHOR]

In recent years, magnesium slag has been used as a raw material for solid waste treatment using the carbonization method and has proven to be promising in reducing carbon emissions. In this study, the alkali activation reaction was introduced to promote the carbonization of magnesium slag. The resulting mechanical properties, microstructural attributes, and carbonization mechanism were studied by varying the sodium hydroxide content, temperature, and carbon dioxide concentration during the reaction process. The results showed that the amounts of calcium hydroxide, C-S-H, and calcium carbonate in the reaction products increased with the sodium hydroxide content, which enhanced the compressive strength of the composite. However, it does not influence the carbonization mechanism with the increasing reaction temperature, which only elevates the reaction rate. With the increase in the carbon dioxide concentration during alkali activation, the carbonization reaction is dominated by the amount of CO2 dissolved in the reaction medium, and the carbonization mechanism is changed. Thus, a significant decrease in the calcium hydroxide content and a sharp increase in the calcium carbonate content in the products occurred, which significantly improved the compressive strength of the resulting magnesium slag composite. Among them, the maximum compressive strength is 6.83 MPa. [ABSTRACT FROM AUTHOR]

Microplastics (MPLs) and nanoplastics (NPLs) are smaller particles derived from larger plastic material, polymerization, or refuse. In context to environmental health, they are separated into the industrially-created "primary" category or the degradation derivative "secondary" category where the particles exhibit different physiochemical characteristics that attenuate their toxicities. However, some particle types are more well documented in terms of their fate in the environment and potential toxicological effects (secondary) versus their industrial fabrication and chemical characterization (primary). Fourier Transform Infrared Spectroscopy (FTIR/µ-FTIR), Raman/µ-Raman, Proton Nuclear Magnetic Resonance (H-NMR), Curie Point-Gas Chromatography-Mass Spectrometry (CP-gc-MS), Induced Coupled Plasma-Mass Spectrometry (ICP-MS), Nanoparticle Tracking Analysis (NTA), Field Flow Fractionation-Multiple Angle Light Scattering (FFF-MALS), Differential Scanning Calorimetry (DSC), Thermogravimetry (TGA), Differential Mobility Particle [Sizing] (DMPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Scanning Transmission X-ray Microspectroscopy (STXM) are reviewed as part of a suite of characterization methods for physiochemical ascertainment and distinguishment. In addition, Optical-Photothermal Infrared Microspectroscopy (O-PTIR), Z-Stack Confocal Microscopy, Mueller Matrix Polarimetry, and Digital Holography (DH) are touched upon as a suite of cutting-edge modes of characterization. Organizations, like the water treatment or waste management industry, and those in groups that bring awareness to this issue, which are in direct contact with the hydrosphere, can utilize these techniques in order to sense and remediate this plastic polymer pollution. The primary goal of this review paper is to highlight the extent of plastic pollution in the environment as well as introduce its effect on the biodiversity of the planet while underscoring current characterization techniques in this field of research. The secondary goal involves illustrating current and theoretical avenues in which future research needs to address and optimize MPL/NPL remediation, utilizing nanotechnology, before this sleeping giant of a problem awakens. [ABSTRACT FROM AUTHOR]

In this work, a plasma-assisted solvolysis method is proposed as an alternative method for the oxidative degradation of carbon fiber-reinforced composites (CFRCs). Nitrogen plasma ignition within bubbles in a concentrated nitric acid solution is employed, combining the synergistic effects of traditional nitric acid solvolysis and plasma chemistry. A comprehensive process flowchart, including steps such as composite pretreatment, matrix dissolution, fiber recovery and cleaning, solvent regeneration and reuse, and waste treatment, is also discussed, highlighting their importance in process effectiveness. Moreover, a study on the effect of the composite's mass on the plasma-enhanced solvolysis process is conducted, and the results are exploited for the calculation of critical parameters such as efficiency, recovery rates, capacity, fibers quality, energy consumption, consumption of raw materials, operational and installation costs, and environmental impact. A preliminary comparison to other recycling methods based on the literature findings is also attempted, and preliminary metrics to assess the sustainability of the recycling process are proposed. [ABSTRACT FROM AUTHOR]

The pollution caused by the mining and smelting of heavy metals is becoming an increasingly severe environmental problem. In this study, the environmental risks of mine tailings were explored using typical antimony tailings (the depth of the sample taken from the ground to the deepest position of 120 cm) from the Zuoxiguo mine in Yunnan Province, Southwest China. The tailings were examined to explore the geological background, distribution characteristics, and release characteristics of heavy metals. Additionally, stabilizer treatments for heavy metals were investigated in consideration of waste treatment. The results showed that the contents of Sb and As (8.93×103 and 425 mg/kg, respectively) in the tailings were considerably higher than the local soil background values, suggesting that these metals pose a considerable threat to the surrounding environment. The geological background values of Cr, Cd, Pb, Cu, and Zn were relatively low. The results of static release showed that Sb, As, Cd, and Cr leached from the tailings more easily than Cu, Zn, and Pb under acidic conditions (pH=2.98). Geo-accumulation indices and potential ecological risk indices showed that Sb, As, Cd, and Pb were highly enriched in the tailings, whereas Cu, Cr, and Zn contents were relatively low. The single factor ecological risk index of the mining area showed that Sb and As are high ecological risk factors, whereas Cr, Cu, Zn, Cd, and Pb are not. The results of the orthogonal test results showed that by adding 15.0% (m/m) fly ash and 15.0% (m/m) zeolite powder to the quicklime and curing for 28 d, a significant stabilization effect was observed for Sb, As, and Pb. This study helps determine the priority control components for characteristic heavy metals in antimony tailings, and provides valuable insights regarding the formulation of appropriate mitigation strategies. [ABSTRACT FROM AUTHOR]