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Ocean disposal of industrial waste from technical DDT [mainly 1,1-(2,2,2-trichloroethane-1,1-diyl)bis(4-chlorobenzene), or 4,4-DDT] manufacture occurred historically in the Southern California Bight. However, the paucity of historical records highlights uncertainties as to the mode, location, and timing of disposal or ongoing ecological effects of these wastes. This study combines sampling, chemical analysis, and numerical modeling of deep San Pedro Basin sediments revealing substantial DDT contamination that extends at least 25 km from the mainland. These findings narrate bulk DDT waste disposal to the offshore that peaked in the 1950s, prior to the onset of formal regulations; was agnostic to later-designated disposal sites; and has experienced sluggish transformation. Our findings further indicate an attenuating secondary source for the DDT daughter product, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene (4,4-DDE), which still deposits into deep San Pedro Basin sediments. While demonstrating the severity of DDT contamination to the region, these findings further define the burial potential of DDT wastes and inform the past, present, and future contamination potential that is needed to understand and predict ecological consequences. This work also points firmly to bulk, not containerized, disposal of DDT waste and to potential alternative contents of collocated waste.

Superhydrophobic materials, known for their exceptional water-repellent properties, have found widespread applications in diverse fields such as self-cleaning surfaces, anti-icing coatings, and water-resistant textiles. In recent years, researchers have explored a sustainable approach by repurposing waste materials to create superhydrophobic surfaces. This eco-friendly approach not only reduces environmental impact but also aligns with circular economy principles, contributing to a more sustainable future. Creating superhydrophobic materials from waste involves a combination of surface modification techniques and hierarchical structuring, with rigorous characterization to ensure the desired properties. These materials showcase their potential in various industries, opening doors to more environmentally friendly technologies. This review delves into the concept of superhydrophobic materials derived from waste and the methods used for their synthesis. It begins by defining superhydrophobicity and highlighting its unique characteristics. It emphasizes the pivotal role played by superhydrophobic materials across industries. The review then explores waste materials’ untapped potential, discussing the advantages of harnessing waste for superhydrophobic material development. Concrete examples of promising waste materials are provided, including agricultural residues and industrial byproducts. The review outlines five key sections that will be further developed to offer a comprehensive understanding of this innovative and sustainable approach to superhydrophobic materials.

Abstract Circular economy (CE) has attracted considerable attention from governments, policymakers, and societies due to its potential to promote sustainable development goals while shifting away from linear economy models. Despite a growing body of research conducted in the CE, the barriers to its successful implementation for solid waste management (SWM) remain less explored especially in context of municipal solid wastes, and commercial and industrial wastes. The purpose of this current study is to identify the critical barriers to circular economy implementation in SWM. The scientometric analysis of literature is the research methodology in this study. A total of 1709 journal articles were searched and retrieved from Scopus database for the data analysis. The results show that circular economy has not gained much root in solid waste management in the global south. Countries such as China, United States, Australia, Italy, and United Kingdom (UK) are the topmost countries to fund research in this research area. The commonly used keywords in scholarly literature on this topic include sustainability, reuse, waste management and recycle. Further, the major findings of the study were grouped into clusters relating to challenges on macroeconomic policies, recycling and reuse of waste, stakeholder management, operation, and legal regulations, generated solid wastewater treatment, and construction and demolition waste. The contributions of this research are twofold: a comprehensive list of relevant gaps for further studies are provided for the scientific community to delve into this matter and proffer solutions. The findings could serve as a guide to understand and develop best practice framework on circular economy and its implementation in the SWM.

The waste generated during ceramic polishing is typically disposed of in landfills rather than being recycled within the production facility, potentially causing environmental harm. This study aims to enhance industrial waste utilization and reduce CO2 emissions in the cement industry by investigating the feasibility of incorporating ceramic sludge from polishing processes into an innovative binary blended cement. Different binders were prepared with varying amounts of ceramic polishing sludge (CPS), ranging from 10% to 50%, and tested against the ASTM C595 standards. The results were compared with those of ordinary Portland cement (OPC). This approach involves evaluating the pozzolanic activity and conducting an advanced characterization assessment of CPS and binary blended ceramic polishing sludge cement (CPSC) paste. This study employed a combination of physical, mechanical, and chemical tests, including setting time, particle size distribution (PSD), Brunauer-Emmett-Teller (BET) specific surface area, compressive strength, X-ray diffraction (XRD), scanning electron microscopy (SEM), heat of hydration, and differential scanning calorimetry/thermogravimetric analysis (DSC/TGA). The results indicated that CPS can be used as a pozzolanic material to create innovative binders with properties comparable to those of OPC. The Strength Activity Index (SAI) values affirmed the pozzolanic properties of CPS, exceeding 75% for up to 40% CPS replacement. Incorporating CPS in the blended cement resulted in a slower rate of cement hydration, leading to prolonged setting times and reduced early strength development. Although the compressive strength decreased with increasing CPS content, it remained within the acceptable ASTM C595 limits with up to 50% replacement. Nevertheless, the optimal replacement level of OPC with CPS was determined to be 50%. Furthermore, CPS substitution reduced the dry density and improved the water absorption and apparent porosity, reflecting microstructural changes. The SEM images revealed that the blended CPSC had a lower apparent porosity than the pure OPC. The DSC/TGA analysis demonstrated that the blended cement had a lower calcium hydroxide content and higher silica than pure OPC.

• Sulphate decomposition by galvanic sludge calcination forms a spinel solution. • The amount of kaolin and red clay influences the formation of a spinel solid solution. • Reuse of 300 tons/year of galvanic sludge helps Amazonian rainforest preservation. • Amazonian clays guarantee the sustainability of a highly toxic environment. This study presented the influence of two types of clay: kaolin (Kao) and red clay (RC) on the chemical and physical properties of ceramic specimens when galvanic sludge (GS) is incorporated to encapsulate heavy metals. Samples were obtained of GS from the industrial district of Manaus – Amazonas State, Brazil, and kaolin (Kao), and red clay (RC) from the Central Amazon. A fourth sample was prepared by mixing GS, Kao, and RC in the ratio 1:1:8 (GS + Kao + RC). This mixture was ground, and ceramic specimens were prepared, and heat treated at 950 °C and 1200 °C for three hours for phase detection, compressive strength, leaching of Fe, Ni and Cr metals and life cycle assessment. Galvanic sludge, Kao, and RC were also, and heat treated to at 950 °C and 1200 °C for three hours, obtaining GS950, GS1200, Kao950, Kao1200, RC950, and RC1200. The samples were submitted to XRF, XRD, Rietveld refinement, Mössbauer spectroscopy, TG/DTG/DSC, and SEM. The results show that the formation of nickel oxide and a spinel solid solution of the type F e 3 + { F e 1 - y 3 + , F e 1 - x 2 + , N i x 2 + , C r y 3 + } O 4 (in which [] = tetrahedral site, {} octahedral site) occurs in GS1200, which is caused by sulfate decomposition to SO 2. At 1200 °C, heavy metals are encapsulated, forming other phases such as nickel silicate and hematite. Life cycle assessment was used to verify the sustainability and value of GS in clay for making bricks, and it indicated that the production of ceramics is feasible, reduces the use of clays, and is sustainable. [ABSTRACT FROM AUTHOR]

In this study, the effects of different sintering methodology on grain formation, density, and hardness of blended leach residue (B‐LR) pellets is investigated. For the first time, the flash sintering (FS) method, an environmentally friendly process, is used to make multiphase ceramic composites using B‐LR under 100 V/mm at 675∘$^\circ $C. The outcomes of this study revealed that the FS process is faster and more energy‐efficient than the conventional sintering (CS) methods performed at 800°C for 4 h. The formation of abnormal grain growth is prevented by FS in B‐LR material composition after it is exposed to a max power absorption 61.4 mW/mm3 and whole FS is completed less than 100 s. Besides, FS method does not lead to any melting on grain boundaries due to excessive joule heating, compared with the CS sample. It is noted that FS also provides better density and hardness values for this material system along with compositional integrity in this multiphase system. The significant outcome of this study is reducing lead volatility and emission by decrement on the sintering temperature. Ultimately, this study has planned the practicality of reusage and recycle of this material with green, safe, and eco‐friendly methods. [ABSTRACT FROM AUTHOR]

Replacement of industrial byproducts as the main components of concrete has gained the attention toward the environment in reducing the raw material consumption. Fly ash (FA) cenosphere is one such industrial product used in the concrete as a partial or full replacement of fine aggregate, which can be able to use for non‐structural applications. Whereas for structural applications, reinforcement in the concrete and their bond behavior is an essential factor that influences its structural behavior. Hence, this study explores the bond behavior of plain and deformed rebar, 10 and 12 mm, respectively, in concrete containing 0%, 25%, 50%, 75%, and 100% FA cenosphere as fine aggregate. A pull‐out test is performed to study the bond behavior experimentally and the results show that the bond strength decreases with increase in the diameter of the rebar irrespective of concrete's compressive strength. The deformed rebar showed a better performance than the plain rebar with an average bond stress of nearly 60%. Finite element analysis has been performed using ANSYS‐ 2022R2 to validate the experimental results with simulated results in which the error percentage is in line with good results. [ABSTRACT FROM AUTHOR]

This article a synthesis of humic acid with the obtaining of potassium humate based on coal waste from the Lenger deposit. Accumulated industrial waste heavily pollutes the environment and has a direct impact on all living things. The accumulation of waste in landfills increases the pollution level of the atmosphere, soil, groundwater, and surface water, destroys the functioning of ecosystems, and damages agriculture and construction. A sieve analysis was carried out to study the fine fractions of coal waste, and a scanning electron microscope analysis was performed to study the mineralogical, structural state and X-ray chemical phase composition. The chemical composition of coal waste was studied using differential thermal analysis during heat treatment. The optimal parameters of the process for obtaining humic acids are established, and the results of experimental work are presented. The results are confirmed by mathematical planning of the experiment using the method of orthogonal plan of the second order. The mathematical planning results were tested according to the Student and Fischer criteria. Based on the conducted studies, it was identified that the degree of extraction of humic acid reaches up to 95.90% in terms of the organic phase, and the concentration of humic acid is 49.13%. From the humic acids obtained using potassium hydroxide, potassium humate was synthesized. The potassium humate obtained in its composition has fertilizer properties. Therefore, the obtained potassium humate will be used for the production of humic fertilizers to improve soil fertility and crop yields. The synthesis of humic acids with the production of potassium humate is aimed at reducing the accumulated industrial waste, which in turn allows you to regulate and improve the ecological situation and green ecology in the region.

In the work there were presented results of investigations of physico-water properties and water retention ability of chosen post industrial waste in the aspect of natural management. Soil water characteristic curves were determined in pressure chambers with porous ceramic plate and parametrized to the van Genuchten equation. The obtained results show, that the less advantageous retention ability has flotation waste and coal mud, the medium one metallurgical and soda waste. The best retention properties have energetic and heat energetic waste. The determined soil water characteristic curves can be the base for evaluation possibilities of natural management of the investigated waste. The carried out investigations, supplemented by examination of chemical properties enable to choose optimal methods of biological reclamation of landfills where are deposited.

This study explores the effects of incorporating palm oil fuel ash (POFA) and fly ash (FA) as partial cement substitutes on the mechanical properties and characteristics of high-quality mortar, specifically Engineered Cementitious Composites (ECC). ECC mortar was fabricated by milling POFA waste and FA through a top-down method utilizing a ball mill. The resulting material was subjected to tests for slump flow, water absorption, compressive strength, and characterized through XRF, FTIR, SEM/EDX, and XRD analyses. FTIR analysis verified the existence of Si-O and Al-O groups within the composite made of POFA-FA ECC. XRF analysis of FA and POFA showed cementitious properties, with SiO2+Al2O3+Fe2O3 exceeding 50% and CaO surpassing 10%. SEM and XRD results indicated minimal cavity formation, suggesting a high compressive strength in the mortar. Particle size distribution analysis revealed prevalent particles in the 1.5×10−1 to 2.0×10−1 μm range. The compressive strength test after 28 days, incorporating 15% FA and 10% POFA, yielded the highest strength at 59.30 MPa. The water absorption values ranged from 1.25% to 2.67%, indicating that POFA-FA assists in the cement hydration process and also serves as a filler. As a result, the material’s density is very high, leading to fewer voids formed, thus reducing the trapped water, which significantly affects the mortar’s strength.

Currently, one of the urgent socioeconomic and demographic tasks of the Russian Federation is the implementation of a longterm program for the resettlement of citizens to remote Far Eastern and Arctic territories of the country. Nevertheless, the almost six-year period of the special «Far Eastern» legislative act has not shown good results. One of the numerous reasons for this, according to the author, is the insufficient accounting of lands contaminated by production and consumption waste in the Federal Information System «nadalniyvostok.rf» (hereinafter – FIS), in which land plots for citizens – potential owners of Far Eastern hectares and Arctic hectares – are presented as suitable for development. Purpose: to analyze legal and socio-environmental problems related to the development of the «Far Eastern hectare» and «Arctic hectare» programs, land pollution by industrial and municipal (or household) waste, «accumulated environmental harm» of the Arctic zone of Russia. Methods: comparison, description, formal and dialectical logic, legal-dogmatic and interpretation of legal norms. Results: the study reveals the shortcomings of organizational and licensing activities of municipal and regional authorities of the Far Eastern and Arctic regions, as well as the Federal Registration Service (Rosreestr) bodies related to the implementation of the «Far Eastern hectare» and «Arctic hectare» programs. On the one hand, in order to eliminate the identified problems, it is necessary to clarify and adjust the location of the land plots designated in the FIS for the realization of citizens’ rights to the Far East hectare and Arctic hectare. On the other hand, the study highlights the need to better identify the areas of accumulated environmental damage and production and consumption waste disposal, as well as to adjust the regional legislation to avoid the allocation to the «Far East Hectare» program of territories previously used for the production and consumption waste disposal.

Over the years, the Shaying River Basin has experienced frequent instances of river pollution. The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying River has transformed it a major tributary with relatively serious pollution challenge within the upper reaches of Huaihe River Basin. To study the sources of manganese (Mn), chromium (Cr), nickel (Ni), arsenic (As), cadmium (Cd) and lead (Pb) in Shaying River water, 123 sets of surface water samples were collected from 41 sampling points across the entire basin during three distinct phases from 2019 to 2020, encompassing normal water period, dry season and wet season. The primary origins of heavy metals in river water were determined by analyzing the heavy metal contents in urban sewage wastewater, industrial sewage wastewater, groundwater, mine water, and the heavy metal contributions from agricultural non-point source pollution. The analytical findings reveal that Mn primarily originates from shallow groundwater used for agricultural irrigation, While Cr mainly is primarily sourced from urban sewage treatment plant effluents, coal washing wastewater, tannery wastewater, and industrial discharge related to metal processing and manufacturing. Ni is mainly contributed by urban sewage treatment plant effluents and industrial wastewater streams associated with machinery manufacturing and metal processing. Cd primarily linked to industrial wastewater, particularly from machinery manufacturing and metal processing facilities, while Pb is predominantly associated with urban sewage treatment plant effluents and wastewater generated in Pb processing and recycling wastewater. These research provides a crucial foundation for addressing the prevention and control of dissolved heavy metals at their sources in the Shaying River.

MgO–C refractories are employed as linings for high–temperature containers where they are susceptible to thermal shock and oxidation. In this work, the oxidation behavior of low–carbon MgO–C refractories under thermal cycling was investigated for the first time, and the potential utilization of TiB 2 –BN–AlN (TBA) industrial waste as an additive was also investigated. The results showed that the traditional antioxidant Al was basically ineffective under the condition of thermal cycling; however, the incorporation of TBA industrial waste effectively maintains exceptional oxidation resistance, regardless of thermal cycling. This can be attributed to its capacity to seal the porosity, prevent oxygen intrusion, and absorb elastic strain energy while reducing stress. Additionally, when exposed to an oxidizing atmosphere, MgO–C refractories containing only TBA industrial waste exhibit a low thermal expansion coefficient. [ABSTRACT FROM AUTHOR]

Numerous tons of hazardous wastes containing persistent organic pollutants (POPs) are stored in an unsafe manner in the petrochemical industries. The planetary ball mill causes the formation of mineral Cl compounds during the degradation of polychlorinated compounds in the presence of various reagents. In addition, the planetary ball mill has been applied for the synthesis of diverse organic-inorganic hybrid nanomaterials. In the present study, Fe-metal organic framework was prepared using a planetary ball mill, and then Fe@C nanocomposite with core/shell structure was synthesised by carbonisation. X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) were utilised to study the synthesised materials. The nanocomposite was used as a reagent to degrade persistent organic pollutants in the sludge of a petrochemical wastewater treatment plant by a planetary ball mill. CaO was also used to compare the effect of nanocomposites on system performance. Ion chromatography (IC) analysis was carried out to determine chlorine mineralisation. Furthermore, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy were applied to determine chemical bonds. The results illustrated a zero-valent iron nanoparticle in the core protected by carbon shell in a synthesised nanocomposite with a core/shell structure. Hence, nanocomposite was the most efficient additive, with 97% dechlorination efficiency in the first hour while the efficiency of the planetary ball mill in the presence of CaO was only 76% after 12 hours of milling. Furthermore, major changes occurred in the organic phases, carbon and chlorine bonds. Simultaneously, graphite and amorphous carbon were produced in the final products after milling. This indicates that aromatic structures and C-Cl bonds were broken down into inorganic compounds. Thus, this study presented a practical method of producing materials while degrading hazardous pollutants in petrochemical wastewater sludge through a planetary ball mill. [ABSTRACT FROM AUTHOR]

The production of ceramic tiles is an intricate process of combining modern technology with ancient craftsmanship, which creates versatile and durable finished surfaces for various construction applications. The manufacturing of ceramic tiles causes the production of significant waste during different production stages such as shaping, firing, and finishing leading to environmental degradation and depletion of resources. Therefore, this research work was planned to investigate the possibility of utilizing ceramic waste in the manufacturing of ceramic tiles. Two types of ceramic waste, namely glaze waste and body waste were used with 5–10% replacement of different materials in the production of ceramic tile. The results revealed that up to 10% of the waste produced during the manufacturing of ceramic tiles can successfully be reused in the manufacturing of ceramic tiles. The ceramic tiles produced with 10% replacement of feldspar satisfied the minimum criteria of flexural strength, shrinkage, and water absorption supported by scanning electron microscopy findings. Moreover, a machine learning model was developed using six input variables, i.e., feldspar (F), three different types of clays (C1, C2, and C3), body waste (BW) and glaze waste (GW), while three variables, i.e., firing shrinkage (S F), flexure strength (FS) and water absorption (WA), as output. Applying a machine learning approach to data revealed that the model, i.e., artificial neural network (ANN), exhibited strong and consistent performance, displaying notable generalization capabilities (with an R2 greater than 0.95 on the test set). This study aims to shape sustainable waste management approaches and establishes a blueprint for harnessing ceramic waste with the potential to be a primary resource in the production of ceramic tiles. [ABSTRACT FROM AUTHOR]

This study offers essential metrics for informed decision-making in the context of transforming traditional industrial estates into circular economies. The study conducts a systematic analysis of an existing industrial zone, demonstrating its potential transition towards a circular approach while assessing its economic viability and avenues for enhancement. The paper unfolds as follows: It initially presents a comprehensive methodology for quantifying the economic value added through recycling within the industrial zone. Subsequently, it introduces a method to compute the economic value associated with the remaining waste generated within the industrial zone. The paper then proposes a novel approach for determining the circularity factor of an industrial zone, effectively quantifying the degree of circularity achieved within the zone. Finally, it integrates circular economic principles and outlines a framework to assess the circularity value across the entire manufacturing process, reducing waste and reintegrating it into the material supply chain. The study provides a robust methodology for calculating circular value addition within an industrial zone. Furthermore, these metrics are applied to Biyagama Export Processing Zone (BEPZ), in Sri Lanka as part of the study's empirical analysis. The circularity factor of the zone was 0.4, and it clearly identifies that the total economic value addition of the zone can be maximized through the practice of a circular economy.

The phytoremediation technique is gaining excessive consideration as a promising method to remediate industrially contaminated soils with heavy metals. In this study, a pot experiment was performed in which the ornamental plant Helianthus annus L. was grown in the pots with three concentrations i.e., 0, 5, and 10 % of contaminated soil amended with compost (2 %) in all pots of the experiment following three treatments of bacteria i.e., Co, Stutzerimonas stutzeri and Pseudomonas sundara. After sixty days of the experiment, the plants were harvested and morphological, physiological, antioxidants and pollution parameters were investigated. The plant height and biomass of the sunflower were increased by the inoculation of S. stutzeri and P. sundara. Pigments e.g., chlorophyll a, b, carotenoids and proteins of the plants were enhanced. There was an increase in antioxidants e.g., catalase, peroxidase, ascorbate peroxidase and proline content and a decrease in hydrogen peroxide content of plants by inoculation of S. stutzeri and P. sundara. The bacteria boosted the uptake of heavy metals (cadmium, chromium and lead) in parts of plants. Post-harvested soil analysis indicated decreased electronic conductivity, total dissolved solids, bicarbonates and heavy metals in the soil. In the future, the combination of H. annus and bacteria could be a better technique to remediate the heavy metals in industrially polluted soils.

The use of industrial waste red mud in polymer composites promotes environmental sustainability by mitigating the environmental impacts associated with landfill disposal. Previous research by the authors on red mud sisal fiber composites resulted in increased strength; it is expected that the strength can be increased further through fiber treatment. As a result, the current study sought to examine the effects of chemical‐treated sisal fiber reinforcement on the mechanical properties of red mud composites. Alkaline treatment and silane treatment were both used as chemical treatment methods. Red mud was added in three different weight percentages, and composites were built using the compression molding method and tested for hardness, tensile strength, flexural strength, and impact strength. The findings indicate that the strength of the composite increases with the incorporation of treated fibers, silane‐treated 30% red mud composites showed a maximum hardness of around 92 shore D. The tensile strength of the composites containing 20% red mud and treated with silane was the highest, reaching ca. 63 MPa. This significant increase in strength was attributed to the formation of strong interfacial bonding between the red mud, fiber, and matrix. Furthermore, the silane‐treated 20 wt% red mud composites have the highest flexural strength (ca. 244 MPa) and impact strength (ca. 26 J/m). However, increasing the red mud content above 20 wt% resulted in decreased tensile, flexural, and impact strength due to poor bond development, and red mud agglomeration. The findings of this study are beneficial for the design and development of composites based on red mud, as well as for promoting sustainable waste management practices. Highlights: Red mud composites achieve superior mechanical strength.Chemical treatment enhances sisal fiber reinforcement.Sustainable waste management promoted through composite utilization.Strong interfacial bonding improves composite performance. [ABSTRACT FROM AUTHOR]

In the presented work, industrial waste, solid waste and their types and their impact on the environment were investigated. The change of natural environment elements under the influence of waste is shown. The problems of waste generation and use have been investigated. The stages of industrial waste processing are indicated. The theoretical foundations of the transition to waste-free technology have been defined. The role of the latest technologies in improving industrial waste management is explored. A number of proposals have been put forward in this area. [ABSTRACT FROM AUTHOR]

Thermo-chemical conversion of cigarette butt filters (CBF) waste was investigated using various thermal analysis techniques (simultaneous TG-DTG-DTA and DSC methods) at different heating rates in an inert atmosphere. Thermo- and thermophysical properties of waste material were discussed, from the point of view of chemical structure and the influence of experimental parameters on the conversion process. It was established that acetyl groups of plasticizer (triacetin) interact with cellulose acetate through dipolar interactions and hydrogen bonding's. Influence of these polar interactions can affect the position of glass transition temperature, Tg, of CBF. Based on estimated value of Tg from DSC analysis, it was found that cellulose acetate present in CBF has degree of substitution equals to 2.8, where the presence of cellulose triacetate was confirmed. It was assumed that an increase of degree of substitution leads to decline in the crystallinity. A decline of crystallinity causes the reduction of hydroxyl groups, leading to less organized chains, and whereby decreasing of inter-molecular interactions through hydrogen bonding. Based on the examination of thermophysical characteristics of the tested material, it was found that both, the heat capacity and the thermal inertia of material linearly increase with temperature, during pyrolysis progression. It was concluded that the type of bio-char produced in this process would have a large capacity to store the heat, which may depend on the formed particles size diameter and porosity. Furthermore, it was inferred that magnitude drops of thermal conductivity, κ, after Tg depends on the material fibrillation. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the growth of Cerrado seedlings and soil quality using byproducts of sugarcane in a degraded area. The experiment was implemented in the Northwest of Minas Gerais State, Brazil, with the following treatments: (T1) control, (T2) filter cake, (T3) sugarcane bagasse, (T4) filter cake + sugarcane bagasse and (T5) mineral fertiliser. After planting, three evaluations of plant height and diameter at ground level were carried out. The soil quality was evaluated 410 days after planting at 0-10 and 10-20 cm depths, where total and microbial carbon and nitrogen, basal and accumulated respiration, microbial and metabolic coefficient were determined. For Anacardium humile and Hymenaea courbaril, T2 and T3, respectively, favored their growth in diameter. The seedlings of A. humile, Butia capitata and H. courbaril showed the higher growth in height with filter cake and bagasse (T2, T3 and T4). Soil carbon and nitrogen contents were higher in T2 at 0-10 cm, and these variables were more responsive in T1, T2 and T3 at 10-20 cm. The use of sugarcane bagasse and filter cake residues promoted good growth of all the evaluated species and improved soil quality, as indicated in recovery projects for degraded areas. [ABSTRACT FROM AUTHOR]

In this paper, we study the possibility of using industrial waste from the coke industry as a feedstock for the production of geopolymer composites. To activate the process of waste polycondensation into a geopolymer, a wet method was used using NaOH, mixture of NaOH and Na2SiO3, as well as a dry method with an activator Na2SiO3. Fourier transform infrared spectroscopy, thermogravimetry, differential scanning calorimetry, scanning electron microscopy were used to determine the physicochemical features in the obtained geopolymers. It was found that the production of geopolymer composites based on the waste of the coke industry is possible with the use of alkaline activators, the dry method with sodium metasilicate is more preferable. [ABSTRACT FROM AUTHOR]

Industrial waste has a high potential for reuse in the production of refractories, which can significantly lower costs. The purpose of the research is to access the role of three types of recycled industrial wastes (ferro‐titanium slag [FTS], ferhro‐chromium slag [FCS], and ferro‐vanadium slag [FVS]) utilized as aggregate in the traditional Al2O3‐SiC‐SiO2‐C refractories (ASSC). Erosion and corrosion resistance characterization was performed to determine whether these industrial waste‐containing ASSC still perform better than traditional ASSC during service. Based on the results, incorporating FVS into the ASSC was not recommended, its corrosion resistance was significantly reduced due to the presence of excessive liquid phase. Nonetheless, FTS and FCS could be added as aggregate to the ASSC without affecting their performance. This necessity of the proper amount of liquid phase in ASSC was highlighted in this research since the parameters could alter its properties. Furthermore, the Ti(C,N) transformed from TiO2 in FTS via carbothermal reduction nitridation could effectively prevent further corrosion, and Cr2O3 derived from the decomposition of (Al,Cr)2O3 solid solution in FCS could play the same role during the corrosion process, both of which may be potential raw materials to be used in refractories. [ABSTRACT FROM AUTHOR]

The halotolerant non-conventional yeast Debaryomyces hansenii can grow in media containing high concentrations of salt (up to 4 M), metabolize alternative carbon sources than glucose, such as lactose or glycerol, and withstand a wide range of temperatures and pH. These inherent capabilities allow this yeast to grow in harsh environments and use alternative feedstock than traditional commercial media. For example, D. hansenii could be a potential cell factory for revalorizing industrial salty by-products, using them as a substrate for producing new valuable bioproducts, boosting a circular economy. In this work, three different salty by-products derived from the dairy and biopharmaceutical industry have been tested as a possible feedstock for D. hansenii 's growth. The yeast was not only able to grow efficiently in all of them but also to produce a recombinant protein (Yellow Fluorescent Protein, used as a model) without altering its performance. Moreover, open cultivations at different laboratory scales (1.5 mL and 1 L) were performed under non-sterile conditions and without adding fresh water or any nutritional supplement to the cultivation, making the process cheaper and more sustainable. [Display omitted] • D. hansenii can thrive in high-salt containing feedstocks for producing recombinant proteins. • Side-streams with high salt content are used without sterilization in lab-scale fermentations. • No addition of fresh water to the media is needed, waste-streams can be used directly from the source. [ABSTRACT FROM AUTHOR]

There has been an exceptional rise in the number of industries in recent times, resulting in a leap in pollution caused, in addition to a large amount of waste being generated. Industrial pollution affects the entire ecosystem, predominantly the air, water, and soil. Remediation of air, water, and soil from industrial pollutants thus becomes a matter of concern due to detrimental effects. Remediation of the wastes generated by the industries has been carried out by several substances. The present research paper discusses with the use of soil microbial consortia for industrial waste bioremediation. Over the past decades studies have being emphasised on the use of microbial consortia rather than the use of individual strains, with increasing consideration given to environmental sustainability, with the aid of interdisciplinary approaches. An in-depth study has been carried out on the different microbes, used for remediation with special focus on soil microbial consortia. The manuscript also describes at length the benefits of the use of these microbes, different contaminants and wastes for which these have been tested, different kinds of microbial consortia explored, and the limitations and advantages associated with the use of these. The present work helps in understanding the use of microbial consortia as an efficient and promising biomaterial with an edge over other materials for industrial waste remediation. A brief study of the patents in the area of the use of soil microbial consortia has also been carried out in the present work. An analysis of the distribution of patents country-wise, technology main areas, patent publication trend, and top patent applicants and inventors has also been carried to give an idea of the patents pertaining to the application of soil microbial consortia. [ABSTRACT FROM AUTHOR]

The utilisation of seawater (SW) for making concrete appears to be a reasonable alternative to conserve freshwater. This paper investigates the possibility of making seawater mixed concrete (SMC) using cementitious replacement of fly ash (FA) and red mud (RM) to offset the adverse effects of SW in concrete. FA was added by replacing from 10% to 40% by weight of cement and RM from 5% to 20% and compressive strength, split tensile strength and electrochemical properties of concrete were evaluated for different mixes for 7, 28 and 90 days of testing. Analysis of variance method was used to identify the influences of FA, RM and concrete testing age on the SMC properties. The best mix was then finalised using the response surface method (RSM). It was observed that RM and especially FA were very effective in improving SW concrete properties, that is, increasing mechanical strength and controlling corrosion of steel in concrete. The results showed that to successfully utilise SW for making concrete, the best results at the testing age of 90 days were obtained on replacing cement with approximately 40% FA. The novel mix showed approximately 23% increase in compressive strength and 12% increase in tensile strength compared to SWM concrete. In addition, the novel mix electrical resistivity is around 60 kΩcm showing it to be in low corrosion zone. [ABSTRACT FROM AUTHOR]

This comprehensive research aims to examine the numerous industrial and agricultural waste streams involved in biodiesel production, providing insights into its potential, problems, and environmental consequences. Applying industrial and agricultural waste products that include high levels of lipids as feedstocks for biodiesel serves the dual purpose of diverting these materials away from landfills and incineration while converting them into lucrative and environmentally sustainable energy sources. This review comprehensively examines many categories of industrial waste feedstocks, including waste oils and greases, residues generated from manufacturing operations, and byproducts derived from agricultural and chemical companies. This review thoroughly investigates many essential components of biodiesel synthesis from industrial and agricultural waste, encompassing the characterisation of feedstock, pre-treatment procedures, transesterification processes, and purification methods. Considerable emphasis is placed on each feedstock's distinct characteristics and obstacles, fostering a thorough comprehension of the biodiesel manufacturing procedure. The rationale behind implementing this sustainable energy solution is driven by its notable environmental benefits, which include reducing greenhouse gas emissions and facilitating ecological contaminants. Furthermore, this study investigates the economic viability, regulatory considerations, and developing trends within the industry, focusing on the potential of utilising biodiesel created from agricultural and industrial waste to foster a circular economy and optimise resource utilisation. [ABSTRACT FROM AUTHOR]

The mining operation is a challenging field for human development. Deep underground mining has increased as a result of the lack of economic minerals close to the surface of the ground. Mining companies are now thinking of backfilling mine wastes to prevent mine collapse during later and deeper extraction stages due to safety and environmental concerns. The production of waste products (for example, fly ash, slag, and tailings) during the processing of minerals, the production of electricity, and the production of metals is tremendous. There is a wealth of information available on employing fly ash, slag, and mine tailings as a partial substitute for cement, as well as for paste backfilling. Nevertheless, a thorough analysis of the use of industrial waste and mining tailings as mine backfill is mostly absent. This article offers a grave evaluation of the use of mine and industrial. Geotechnical characteristics, backfill material features, and issues relating to strength prediction are all examined. In addition to the aforementioned, the effects of substitute binders, such as industrial waste, are considered when modifying paste backfills utilizing admixture. The paper finished with future paths for mine paste backfilling study, specifically utilizing ordinary and non-natural essences for primary strength growth. Hence, continued use of such engineering waste supplies for mill paste backfilling might benefit from this research. [ABSTRACT FROM AUTHOR]

High-performance sequencing using the Illumina technology has been used to investigate the diversity of prokaryotes in three soil samples (Technosols) selected on the territory of the former tailings of liquid waste of chemical production near the city of Kirovo-Chepetsk, Kirov oblast. The taxonomic richness and phylogenetic diversity of microbial communities formed in the process of regenerative succession of the technogenic landscape, in comparison with alluvial soil (Fluvisols)—a natural analogue of the one that was disturbed as a result of the disposal of waste from a chemical enterprise—is assessed. The analysis of the indicators of taxonomic richness and diversity demonstrate their lower values in the soils formed on waste in comparison with the natural soil of the background site. Twenty-six bacterial and 2 archaeal phyla of prokaryotes are identified, accounting for more than 95% of the number of classified sequences. The phylum Actinobacteria (22–41%) and Proteobacteria (20–26%) dominate. At the level of higher taxa in disturbed soils, compared with the community of natural alluvial soil, trends in the representation of phylum are revealed: a decrease in the proportion of Verrucomicrobia and an increase in the proportion of Cyanobacteria. The greatest differences between the communities of technosols and background soil are revealed at the levels of orders, families, and genera. Common and unique genera have been identified for each of the four microbiomes. The detected differences in the composition and structure of the prokaryotic component of microbial communities of disturbed soils are related to the complex of their physicochemical properties (granulometric composition, pH of soil solution, Corg content, composition of toxicants of industrial origin, humidity regime, etc.) and the nature of vegetation cover. The results are of interest for the development of new approaches in future studies of the relationship of soil microbiota with ecosystem changes caused by human activity. [ABSTRACT FROM AUTHOR]

Waste edible oils are an alternative source of high‐value natural compounds. Vitamin E can be recovered from palm oil refining residues by molecular distillation. However, the presence of other lipophilic molecules compromises the selective separation of vitamin E. Esterification of the free fatty acids can enhance the selective separation of vitamin E by molecular distillation, but the conditions for carrying out the reaction need to be investigated to simultaneously ensure the conversion of free fatty acids and the reduction of vitamin E losses. Thus, this study investigated the effect of the esterification of the industrial waste on the recovery of vitamin E by molecular distillation. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and analysis for fats and oils preconized by the American Oil Chemists' Society (AOCS) were used in the characterization of the industrial waste. Determination of the best condition to carry out the reaction was obtained by a central composite rotational design (CCRD) using the response surface methodology (RSM) and the desirability profile. The results showed that the best condition for the esterification was at 64°C, 213 min, 2 wt.% sulphuric acid, and a 10/1 methanol/free fatty acids molar ratio. This reaction condition achieved 97.9% conversion of free fatty acids and less than 3% of vitamin E loss. The esterification promoted concentration of vitamin E in the residue stream (145.4%) and reduction in the distillate stream (87.8%). Therefore, the obtained results presented a suitable route to obtaining vitamin E concentrate and adding value to an industrial residue. [ABSTRACT FROM AUTHOR]

Circular economy (CE) has attracted considerable attention from governments, policymakers, and societies due to its potential to promote sustainable development goals while shifting away from linear economy models. Despite a growing body of research conducted in the CE, the barriers to its successful implementation for solid waste management (SWM) remain less explored especially in context of municipal solid wastes, and commercial and industrial wastes. The purpose of this current study is to identify the critical barriers to circular economy implementation in SWM. The scientometric analysis of literature is the research methodology in this study. A total of 1709 journal articles were searched and retrieved from Scopus database for the data analysis. The results show that circular economy has not gained much root in solid waste management in the global south. Countries such as China, United States, Australia, Italy, and United Kingdom (UK) are the topmost countries to fund research in this research area. The commonly used keywords in scholarly literature on this topic include sustainability, reuse, waste management and recycle. Further, the major findings of the study were grouped into clusters relating to challenges on macroeconomic policies, recycling and reuse of waste, stakeholder management, operation, and legal regulations, generated solid wastewater treatment, and construction and demolition waste. The contributions of this research are twofold: a comprehensive list of relevant gaps for further studies are provided for the scientific community to delve into this matter and proffer solutions. The findings could serve as a guide to understand and develop best practice framework on circular economy and its implementation in the SWM. [ABSTRACT FROM AUTHOR]

Superhydrophobic materials, known for their exceptional water-repellent properties, have found widespread applications in diverse fields such as self-cleaning surfaces, anti-icing coatings, and water-resistant textiles. In recent years, researchers have explored a sustainable approach by repurposing waste materials to create superhydrophobic surfaces. This eco-friendly approach not only reduces environmental impact but also aligns with circular economy principles, contributing to a more sustainable future. Creating superhydrophobic materials from waste involves a combination of surface modification techniques and hierarchical structuring, with rigorous characterization to ensure the desired properties. These materials showcase their potential in various industries, opening doors to more environmentally friendly technologies. This review delves into the concept of superhydrophobic materials derived from waste and the methods used for their synthesis. It begins by defining superhydrophobicity and highlighting its unique characteristics. It emphasizes the pivotal role played by superhydrophobic materials across industries. The review then explores waste materials' untapped potential, discussing the advantages of harnessing waste for superhydrophobic material development. Concrete examples of promising waste materials are provided, including agricultural residues and industrial byproducts. The review outlines five key sections that will be further developed to offer a comprehensive understanding of this innovative and sustainable approach to superhydrophobic materials. [ABSTRACT FROM AUTHOR]

Engineering slag is a green building material that meets the requirements of contemporary sustainable development, and the solidification technology of residue is particularly important in the practical engineering of resource utilization and environmental protection. In order to reuse the waste soil and industrial waste and reduce the construction cost, the stabilization effect of adding different contents of calcium oxide, blast furnace slag and phosphogypsum to the waste soil of a township road reconstruction project was studied. The unconfined compressive strength test of calcium oxide further clarified the solidification mechanism of residual soil and helped us to obtain the optimal curing ratio. The dry and wet cycle test simulated the influence of temperature and humidity changes on the appearance, quality, strength and water resistance in actual engineering. The experimental results show that the unconfined compressive strength of the sample reaches 1.273 MPa after 7 days of curing when the mixture of 4% calcium oxide (ratio to 100% plain soil) and 16% blast furnace slag (ratio to 100% plain soil) is mixed. When the three materials were mixed, the unconfined compressive strength of 4% calcium oxide (the ratio of 35% phosphogypsum and 65% plain soil) and 16% blast furnace slag (the ratio of 35% phosphogypsum and 65% plain soil) reached 1.670 MPa and 3.107 MPa at 7 and 28 days, respectively. The curing age has a significant promoting effect on the stability of loess. The dry and wet cycle test results conclude that the specimens have good durability and stability. The results of microstructure analysis shows that a large number of ettringite and C-S-H gel were formed in the gelling system, which not only makes the original soil more stable, but also acts as a part of filling pores, and the two work together to support the soil and improve the strength. [ABSTRACT FROM AUTHOR]

Expansive soils are a major concern in geotechnical engineering, especially for light structures, due to swell-shrink behavior with moisture content variation. Lime is broadly used in swelling soil stabilization, but the use of industrial waste is emerging as a sustainable solution. Sugarcane bagasse ash (SCBA) is a by-product of the sugar and ethanol industry, with annual world production of around 10 million tons, and several times it has inadequate final disposal. So, this study presents the first evaluation of the feasibility of utilizing SCBA as a stabilizer for compacted swelling soil. For this purpose, one-dimensional swelling tests were done with compacted bentonite–sand blend/SCBA mixtures molded with distinct proportions (100/0, 93.75/6.25, 87.5/12.5, 81.25/18.75, 75/25), compacted in different dry unit weights (12.75 kN/m3, 13.75 kN/m3, 14.75 kN/m3, 15.75 kN/m3, and 16.75 kN/m3) with water content of 19.5%. Methylene blue index tests assessed the mixture's cation exchange capacity (CEC). The bentonite–sand blend swells up to 16.15% and continues swelling after 72 h. By adding 6.25% or more of SCBA, little or no swelling was perceived after 24 h of testing. Furthermore, the denser the blend is, the more it will expand. However, adding 12.5% of SCBA or more in all samples tested presents one-dimensional swelling lower than 0.5%, with no further swell perceived. In addition, CEC agrees with blend swelling behavior. The swell mitigation is attributed to the presence of MgO and CaO in SCBA, as Mg+2 and Ca+2 can chemically alter the soil through cation exchange, replacing monovalent cations in the clay. [ABSTRACT FROM AUTHOR]

For decades, experts have paid considerable scientific and technological attention to the possibility of recycling waste that has reached nature as a result of mining activities related to natural stone, extracting metal or using foreign matter to recover natural environments. Several authors have shown that many of these types of waste can be vitrified or synthesised with an appropriately designed composition, not just to decrease their size but (as is more interesting from a financial point of view) to produce a wide range of glassy and/or ceramic materials that can have uses in industry and, crucially, in the construction sector (building and public works). In this paper, we conduct a comprehensive analysis of the state of the art, defining the different types of materials and their uses in order to decisively contribute to the circular economy and the zero-waste approach. We analyse the achievements accomplished in recent decades to be able to generate novel innovative ideas for collecting new eco-materials. [ABSTRACT FROM AUTHOR]

This study examines the potential of adding grape skins to red ceramics to evaluate its effect on the physical and mechanical properties of the clayey body. Five compositions were prepared with different percentages of biomass incorporation: 0%, 2.5%, 5%, 7.5%, and 10%. The specimens were conformed using vacuum extrusion in a laboratory extruder, with dimensions of 120 mm in length and a straight section of 30 × 15 mm. After drying, the pieces were sintered in a laboratory muffle furnace at 700 °C, 800 °C, 900 °C and 1000 °C. Chemical, mineralogical, thermal, physical, morphological, and microscopy tests were conducted on the clayey raw materials. An acceptable formulation was achieved by incorporating up to 5% biomass, fired at 900 °C. For water absorption, the incorporation of up to 5% of biomass fired at 700 °C satisfies the normative limits to produce structural blocks and sealing blocks. From 900 °C onwards, it meets the parameter intended for making roof tiles. The linear shrinkage of the pieces fired up to 900 °C is slightly altered by the incorporation of up to 5% of biomass fired under 800 °C are below 2%. The bending strength, at 700 °C there was an increase in mechanical strength directly proportional to the increase in biomass. However, at 800 and 900 °C, there was a gradual decrease in the bending strength. In turn, at 1000 °C, there was a sudden reduction in bending strenght for all formulations with biomass incorporation.

The releasing of wastewater contaminated with direct red 28 (DR28) dye into receiving water is a concern because it is a polyaromatic structure with difficult biodegradation. It results in being persistent in the environment and being toxic to the ecosystem from accumulating through a food chain. Thus, it needs to eliminate DR28 dye from contaminated wastewater. Sawdust beads (SDB) and sawdust mixed with iron(III) oxide-hydroxide beads (SDFB) are prepared and characterized for DR28 dye removals. DR28 dye removal efficiencies are examined with various affecting factors by the batch tests and adsorption–desorption tests, and their adsorption patterns, rates, and mechanisms are determined by isotherms and kinetics models. Moreover, the thermodynamic studies are examined for the temperature effect. SDFB demonstrated a higher surface area and smaller pore size than SDB. SDB and SDFB were uneven shapes and heterogeneous fibrillar structures. Carbon, oxygen, calcium, chloride, sodium, OH, CH, CC, COOH, and CO were found in SDB and SDFB. The points of zero charge of SDB and SDFB were 4.65 and 6.11. The conditions of 3.5 g, 50 ℃, pH 3, 60 mg/L and 2.5 g, 40 ℃, pH 3, 60 mg/L illustrated the highest DR28 dye removals of more than 82 % for SDB and SDFB, respectively. Thus, the material modification by iron(III) oxide-hydroxide improved the DR28 dye removal efficiency of sawdust material. Moreover, they could be reusability more than three times with DR28 dye removal of more than 63 %. SDB and SDFB corresponded to Langmuir and Freundlich models, respectively, and a pseudo-second-order was a good model to describe their adsorption mechanism. Both materials did not favor DR28 dye adsorptions with increasing temperature. Therefore, SDFB was a potential material for removing DR28 dye removal in the industrial wastewater.

A search for new approaches to sulfurous waste utilization is one of the urgent tasks of chemical technology. Thiol-disulfide exchange reaction (TDE) is one of the possible ways to involve technogenic wastes in organic synthesis. Electricity can promote such type of interactions. In this paper, we have studied TDE reactions involving low molecular weight thiols or their dimers under electrochemical conditions. The exchange processes were examined using the model reaction between 1-propanethiol and phenyl disulfide. Electrolysis was performed in the presence of redox mediators such as arylphosphines, substituted amines, o-, p-aminophenols or catechol. These compounds can initiate a TDE process with a formation of unsymmetrical disulfides. 4-Amino-2,6-diphenylphenol was chosen as the most effective redox mediator, which reduces the anodic overvoltage of a thiol oxidation by 1.20 V. The advantage of electrolysis in an undivided cell is the increased yield of target unsymmetrical disulfides due to the possibility of reduction ofhomodimers at the cathode. The involvement of refining waste, such as C3–C4 disulfide oil, in the reaction with substituted thiophenols made it possible to obtain a number of unsymmetrical arylalkyl disulfides with biologically active fragments in a high yield (up to 97%) under indirect electrolysis conditions.

In recent years, sustainable construction materials have gained significant attention, with Self-Compacting Cementitious Mixes (SCCM) emerging as a promising alternative due to its ability to self-settlement. For eco-friendly practices, blending SCCM with waste powders (WPs) not only promotes recycling but can improve efficacy of the mix. Though, the fresh-state behavior of such blends remains insufficiently explored. Therefore, in this study, the fresh-state behavior of self-compacting mortar (SCM) investigated when blended with various WPs, i.e., brick, concrete, flyash, and marble powders distinctly, replacing cement up to 30%. Additionally, waste tire rubber (WTR) fiber is introduced, replacing 10% of the fine aggregate. The rheological characteristics of waste incorporated SCM is investigated through two distinct mix series. In Series I, various WPs substitute a portion of the cement. In Series II, WTR fiber replaces 10% of the fine aggregate, while also partially substituting the cement. The integration of WP and WTR fiber modulate the rheological parameters, notably impacting the static yield stress, dynamic yield stress, and plastic viscosity. Within Series-I, the amalgamation of waste brick and marble powders yielded the peak escalation in both static and dynamic yield stresses, registering increments of 424.02% and 210.24%, respectively, relative to plain SCM. Conversely, in Series-II, solely the waste brick powder marked the zenith in these stresses, recording surges of 351.29% and 119.64% respectively, in relation to the plain SCM. Mix FA30R possesses the lowest rheological parameters making it the best SCM mix. Notwithstanding the augmented exertion necessitated by the WP-augmented mixes to achieve optimal flow, every mix manifested pseudoplastic and thixotropic tendencies. Therefore, these findings underscore the feasibility of waste repurposing in construction endeavors, ensuring field flow prerequisites are met.

Removal of heavy metal ions from industrial effluents using environmental friendly bioadsorbents is currently promising approach. However, removal of manganese metal ion via Moringa stenopetala (M.stenopetala) plant material is not studied yet. Thus, parts of the plant has been studied as bio adsorbents for removing toxic manganese ion from aqueous solutions in batch adsorption model. The maximum percent removal of manganese ion obtained from laboratory synthetic wastewater at equilibrium are 96.05 %, 98.90 % and 97.93 % by M. stenopetala plant leaf, bark and seed, respectively. However, the use of M. stenopetala plant leaf procedures an intensive color with unpleasant odor, which is inauspicious. Therefore, M. stenopental plant leaf was no longer examined for isotherm and kinetics studies. The fitness of adsorption data were confirmed based on the value of correlation coefficient (R2). Thus, adsorption by bark best fits of Temkin model with R2 value of 0.9707, while adsorption by seed follows the Langmuir model with R2 value of 0.9733. Adsorption kinetics result indicates that pseudo second-order model well fitted with R2 value of 0.9912 and 0.9947 for bark and seed adsorbents, respectively. Additionally, the applicability of laboratory-developed method was also evaluated on a multicomponent real sample taken from KK textile industry from Addis Abeba, Ethiopia. After characterization, the percentage removal of manganese ion were 79.53 % and 88.93 % for bark and seed, respectively. This achievement is promising and in a good agreement with the results of single component laboratory synthetic wastes.

In this study, a new method was introduced to analyze industrial mixed waste based on volume. The method was applied to characterize the composition, quantities, and potential economic value of waste generated in the Biyagama Export Processing Zone (BEPZ). It was observed that the composition of industrial mixed waste varied across different industries and processes using the proposed method. Moreover, the investigation into the potential economic value of industrial mixed waste revealed that most waste categories generated were recyclable materials accounting for approximately 89.4% of the total waste generated. As a result, the expected revenue generated from the waste was estimated to vary from USD 0.47–0.67 million per year. The study emphasized the significance of a volume-based approach for analyzing industrial mixed waste, along with the significant potential economic value that can be derived from proper management and valorization of these waste streams within a framework aligned with the principles of Circular Economy. The method will identify the hidden potential to regenerate resource to an optimum utility and value aligned with principles of circular economy potential considering industrial waste. The outcome would be helpful for decision-making on different alternatives as the opportunity cost of not having alternatives gets revealed as an estimated value.

A light weight, high strength and low carbon content are the main characteristics of modern concrete that meet requirements for functionality and environmental considerations of engineering structures. In this study, ultra-lightweight high-strength geopolymeric composites (ULHSGCs) were developed using fly ash cenospheres and hollow glass microspheres as aggregates and ground granulated blast furnace slag and silica fume as binders. This investigation focused on the physical, mechanical and microstructural properties of the ULHSGCs. A series of tests were conducted to examine the influence of the key factors on the flowability, setting times, mechanical properties and microstructure. The various tested parameters included the (1) silica fume content (10 %, 12.5 % and 15 %), (2) Na2O content (5 %, 6 % and 7 %); (3) alkali modulus (1.25, 1.5 and 1.75), (4) fibre type (polypropylene fibre and polyethylene fibre), and (5) fibre length (12 mm and 18 mm). The results showed that the density of the proposed ULHSGCs was less than 1500 kg/m3, while the compressive strength was above 70 MPa and the tensile strain capacity was up to 5.3 %. A higher Na2O content and a lower alkali modulus could provide better mechanical properties and fluidity but with a shorter setting time. The addition of 0.5 vol% fibre could effectively improve the mechanical properties without affecting the fresh properties. Due to good bonding to the matrix, the polyethylene fibres allowed the ULHSGCs to achieve pseudo-strain hardening under tensile or flexural loading.

Guava pomace, an underutilized industrial byproduct from the guava processing fruit juice industry prone to have a wide range of bioactive and functional metabolites which has not been explored. Dielectric Barrier Discharge Atmospheric (DBDA) plasma is a novel non-thermal technology that has been widely used in the food processing field of research. In this study, the effect of DBDA plasma treatment under different treatment combinations i.e, 25 kV, 30 kV, and 35 kV for 5 min, 10 min and 15 min respectively for each voltage, on modification of morphological and biochemical properties of the guava pomace powder on improving the efficiency of extraction yield of biomaterials have been investigated. The response surface model (RSM) was then constructed using the experimental results of Box–Behnken Design (BBD) to obtain the optimal extraction conditions. The predicted optimal extraction conditions for DBDA plasma treatment as 35 kV for 15 min and solvent extraction conditions were determined as 80 °C for 360 min causing an increment of the oil yield up to 16.54% when extracted using solvent extractor with ethanol as a solvent. These results indicate that the DBDA plasma treatment previous to the extraction step extraction process can contribute to reduce the duration of extraction by 120 min, increasing the oil yield by 42.75% and improving the nutritional quality of the oil. This research helps to develop a novel and economical method for improving the extraction yield of oil and to fully valorizing the guava fruit processing industrial waste into biomaterial.