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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]

• 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]

AbstractThis study aims to develop reliable and practical models for estimating the compressive strength and CO2 emission of geopolymer concrete (GPC) using the Gene-expression programming (GEP) technique. Approximately 274 data points on the strength and CO2 emission of GPC using fly ash (FA) and ground granulated blast furnace slag (GGBFS) were used to generate two prediction models considering the effects of 19 input variables. The research results show that the proposed GEP-based models perform well with high correlation coefficients (R > 0.95) and reasonable errors. The parametric study demonstrates that increasing the GGBFS content, the Na2O (dry) content, and the molarity of NaOH solution, and decreasing the FA content, the FA/GGBFS ratio, and the added water or total water/binder ratio could significantly enhance the strength of GPC. Besides, the proposed GEP-based models were used to optimise the mix proportions of GPC concrete with minimisation of CO2 footprint. The range and reasonable values of the FA and GGBFS contents, the alkaline activators, the aggregates, and other parameters were suggested based on the in-depth analyses. This significant reference data source could promote the use of GPC widely in the construction industry as green construction materials for sustainable development. [ABSTRACT FROM AUTHOR]

In glass industry, the evolved gases and fumes from burning the gas fuel absorbed in calcium hydroxide to minimize the pollution of environment. After a period of time, the calcium hydroxide fouled with sulphate and carbonate as action of the absorbed SO3 and CO2 gases. Based on our interest to treatment the solid waste materials, this study intended to convert the obtained waste of calcium hydroxide fouled with gases to valuable products. Firstly, this waste was treated with water, caustic soda and acids. The results confirmed the conversion of waste to pure calcium sulfate by treatment with 6 v/v% sulfuric acid. Secondly, the obtained calcium sulfate was reacted with ammonium dihydrogen phosphate solution for preparation of calcium hydroxyapatite (HAp) nanoparticles. The produced HAp sample was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and N2 adsorption measurements. The obtained findings confirmed that the HAp can be produced after calcination at 700 °C, nanorods-like of sizes ranged from 11 to 15 nm and with main surface functional groups of hydroxyapatite. TGA and DTA data indicated that HAp is thermally stable up to 700 °C. Also, the obtained HAp has Ca/P molar ratio of 1.60 and exhibited high total surface area of 146 m2/g with mesoporous structure which make this material can be used in medical and water purification applications. [ABSTRACT FROM AUTHOR]

To improve the in situ soil stabilization, different chemical additives are used (ion exchange compounds, additives based on H2SO4 or vinyl polymers, and organic additives using lignosulfonates). One interesting alternative is the production of additives from various waste materials. The extensive testing of waste-based blends with soil was performed; the mechanical (unconfined compressive strength (UCS)) and hydraulic (capillary rise, water absorption, and frost resistance (FR)) soil properties were measured. The optimization process led to obtaining additive compositions ensuring high strength and sealing properties: by-pass ash from the ceramics industry, waste H2SO4, pyrolytic waxes/oils from waste mixed plastics, waste tires and HDPE, and emulsion from chewing gum waste. For sandy soil, the following additives were the most promising: emulsion from pyrolytic wax (EPW) from waste PE foil (WPEF) with the addition of waste H2SO4, pyrolytic-oil emulsion from waste tires, EPW from waste mixed plastics with the addition of "by-pass" waste ash and NaOH, EPW from WPEF with the addition of NaOH, and EPW from WPEF reaching up to 93% FR, a 79.6% 7-day UCS increase, and a 27.6% of 28-day UCS increase. For clay: EPW from WPEF with the addition of NaOH, EPW from WPEF with the addition of waste H2SO4, and solely EPW from WPEF reaching up to 7.5% FR, an 80.7% 7-day UCS increase, and a 119.1% 28-day UCS increase. [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]

Background. The development of industry around the world has made the problem of comprehensive processing of industrial waste and the involvement of substandard mineral resources into production urgent. Accumulated industrial waste is considered a complex and labor-intensive work in terms of chemical and particle size distribution. Therefore, the processing of industrial waste from phosphorus production to obtain marketable products is an urgent task. Purpose. Study of the physico-chemical properties of cottrel dust for the production of phosphoruscontaining fertilizers. Methodology. Study of the physico-chemical properties of cottrel dust using modern instrumental equipment. Originality. The scientific novelty of the article lies in the study of the physico-chemical properties of cottrel dust obtained from phosphorus production waste for the phosphorus-containing fertilizers. Findings. It has been determined that the dispersed composition in cottrel dust consists of 90% dust particles with a size of at least 20 microns, and 10% mechanical entrainment. It was revealed that at a temperature of 989.21 0C the mass loss of cottrel dust is 4.12% of the total mass. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

Agricultural waste and trash are a universal issue which requires extensive working to reduce the impact. Improper management of agricultural waste can lead to serious environmental problems such as soil contamination, water pollution and air pollution. Lipases (protein-based catalyst) were produced with industrial and agriculture by products through solid-state fermentation. Among indigenously isolated strains, procured from Mycology and biotechnology research laboratory, Aspergillus niger (MBL-14) exhibited the highest lipase production, i.e., 7.5 ± 0.63a U/ mL. Various cultural conditions were optimized for maximum production of extracellular lipases. Among various basal substrates, rice bran supported the highest yield of 8.67 ± 0.29a U/mL, ammonium nitrate 6.1 ± 0.95a U/ mL, with the use of sodium chloride 6.1 ± 0.95a U/mL, sucrose 8.0 ± 0.87aU/ mL, the beef extract 9.1 ± 0.84a U/ mL. Maximum extracellular lipases production (9.3 ± 0.55a U/ mL) was achieved through fermentation optimization over a 48-h period, and an increased lipases output (9.6 ± 0.34aU/mL) was obtained at a moistening agent’s pH level of 8. Incorporation of oil additives revealed that coconut oil yielded the maximum production (11.0 ± 0.91aU/ mL). Finally, the enzyme was subjected to characterization, at pH 9 after a 1-h incubation period, the enzyme activity was highest, and enzyme was stable. After 40 °C (10.6 ± 0.88aU/mL), the enzyme activity starts decreasing and reaches its lowest at 70 °C. When exposed to the cadmium chloride, the crude enzyme exhibited the highest lipase production (10.1 ± 0.76a U/mL and 10.72 ± 0.85a U/mL) before and after a 1 h of incubation, respectively. [ABSTRACT FROM AUTHOR]

The creation of ultra-high-performance concrete (UHPC) requires a huge amount of cement. However, the production of cement raises environmental concerns related to non-renewable resources, carbon dioxide emissions, and global warming. To overcome these issues, it was necessary to expand the production of eco-friendly, sustainable ultra-high-performance concrete (SUHPC) by applying procedures to minimize cement use. This research was able to produce SUHPC with compressive strengths ranging from 168 to 233 MPa at 91 d under standard curing by employing industrial wastes such as granite dust, ceramic powder, and glass powder as a partial replacement of cement by about 26% of its weight, in addition to using crushed granite, ceramic, and glass as a 50% and 100% by volume substitute for sand within the concrete mixture. The influence of these industrial wastes on the mechanical and physical characteristics of SUHPC was investigated. Additionally, the temperature studies on the SUHPC containing industrial wastes and the analysis of the microstructure were presented. The study revealed that replacing some of the cement with granite powder and all of the sand with crushed granite in the SUHPC mixture led to the highest compressive strength, splitting tensile strength, flexural strength, and modulus of elasticity. Specifically, the mixture achieved 196.7 MPa compressive strength, 21.9 MPa splitting tensile strength, 30.3 MPa flexural strength, and 61,010 MPa modulus of elasticity after 28 d. Furthermore, the replacement significantly improved the SUHPC's physical properties. For instance, it reduced water permeability by 18.83%. However, adding glass to the SUHPC mixture negatively impacted both its mechanical and physical characteristics. • The effect of utilizing waste such as granite dust, ceramic powder, and glass powder as partial substitutes for cement to produce SUHPC was investigated. • The effect of the utilization of crushed industrial waste such as granite, ceramic, and glass as partial substitutes for sand in the production of SUHPC was investigated. • Industrial waste replaced 26% of the weight of cement and 50% of the weight of sand. • The mechanical and transport properties, high-temperature resistance, and microstructure of SUHPC were comprehensively analyzed. [ABSTRACT FROM AUTHOR]

This study investigates the efficacious utilization of sludge as a subgrade filler through in-situ shallow stabilization, employing cementitious industrial waste materials including steel slag (SS), fly ash (FA), and calcium carbide residue (CCR) as binding agents. The primary emphasis lies in the evaluation of the macro unconfined compression strength of stabilized sludge over a seven-day curing period, facilitated by a quadratic polynomial response surface model to determine the optimal composite stabilizer (WZ01) proportions. Furthermore, an array of meticulous microstructural analyses encompassing X-ray diffraction, X-ray fluorescence, scanning electron microscopy, and energy-dispersive spectroscopy were undertaken to elucidate the development of internal cementitious products and the intrinsic mechanisms underpinning sludge stabilization in tandem with WZ01. The findings ascertain that the optimum WZ01 composition stands at SS: FA: CCR = 32:28:40. Prominent mineralogical constituents within the stabilized sludge encompass amorphous calcium silicate hydrate, calcium aluminate hydrate, and crystalline ettringite. The amelioration in stabilized sludge properties stems from intricate processes involving ion exchange, hydration reactions, and pozzolanic activities. Significantly, the WZ01 curing agent demonstrates heightened cost-effectiveness and environmental merits compared to conventional Portland cement. [ABSTRACT FROM AUTHOR]

The substantial development of the dyeing and printing industry has resulted in an increased discharge of dye wastewater containing a large amount of recalcitrant organic pollutants. Furthermore, the landfill disposal of red mud has led to significant environmental pollution such as soil erosion and groundwater contamination. Therefore, this study aimed to promote the resource utilization of red mud by preparing advanced oxidation catalyst, resulting in effective treatment of dye wastewater, and the primary reaction mechanism was revealed. In this study, biochar-loading red mud (RBC) was applied to activate persulfate (PDS) for the degradation of acid orange 7 (AO7) with the initial concentration of 50 mg L−1. The maximum removal rate of 2.45 mg L·min−1 was achieved in 20 min and corresponding with the removal ratio of 98.0% under the PDS concentration of 20 mM (4.76 g L−1). Eventually, the removal ratio of 99.2% was attained within 60 min. The high catalytic efficiency was probably ascribed to the singlet oxygen (1O 2) dominant non-radical pathway and RBC-mediated electron transfer mechanism. It was found that Fe(II), specific surface areas and functional groups on the catalyst were highly related to its catalytic efficiency and passivation. RBC had better reusability due to the loading of biochar and the reduction of zero-valent iron. The non-radical pathway mechanism and electron transfer mechanism were proposed for the activation of PDS, and non-radical pathway played a dominant role. Besides, the degradation pathways and toxicity assessment were analyzed. This research proposed a new electron transfer mechanism for activation process of PDS , which can provide a theoretical support for further studies. Overall, this study demonstrated that catalysts synthesized from red mud and biomass exhibit highly efficient activation in degrading the model pollutant AO7 through PDS activation. The catalyst displayed promising reusability and practical applicability, offering potential advancements in both the resource utilization and reduction of red mud. • Resource utilization of red mud and efficient degradation of AO7 were promoted. • Fe° has been identified by the HNO 3 preparation of catalyst. • The non-radical pathway combining 1O 2 and electron transfer has been revealed. • The electron transfer characteristics of the catalyst have been investigated. [ABSTRACT FROM AUTHOR]

The manufacturing of mullite porous ceramics with high strength and low thermal conductivity was achieved through foam gel-casting processes using fly ash coated with alumina sol layers. This research aimed to investigate the effect of alumina sol concentration on foaming slurry rheology, as well as the influence of alumina sol coating layers on the microstructure, phase compositions and properties of the resulting mullite porous ceramics. Increasing the alumina sol concentration from 5 to 20 wt% improved both the viscosity and thixotropy of the foaming slurries while enhanced the shear thinning behavior. Porous ceramics prepared with fly ash coated with alumina sol exhibited smaller pore size compared to the untreated fly ash porous ceramics. Moreover, the distribution of pores gradually became more homogenous in the porous ceramics with treated fly ash. Meanwhile, the weight-reduction, compressive strength and thermal insulation properties of the porous ceramics were improved significantly. The use of fly ash coated with alumina sol (with a concentration of 20 wt%) in the preparation of porous ceramics resulted in the formation of mullite whiskers within the pore walls. This created micron-size gaps between the whiskers, greatly enhancing the thermal insulation of the porous ceramics. Finally, the porous ceramics that were prepared using fly ash coated with alumina sol (with a concentration of 20 wt%) and sintered at a temperature of 1400 °C had a bulk density of 0.45 g/cm3, a compressive strength of 8 MPa, and a thermal conductivity of 0.15 W/m·k. • Fly ash coated with alumina sol for optimizes the rheology of foaming slurry. • Pore distribution became more homogenous in porous ceramics with treated fly ash. • Alumina sol layer can improve strength and thermal insulation of porous ceramics. [ABSTRACT FROM AUTHOR]

[Display omitted] • This review focused on the recycling of solid waste in various industries, including energy applications, water treatment, cement production, and fertilizer manufacturing. • Recovering value from solid waste, agricultural, industrial, and sea waste was introduced. • Solid waste management is effective and efficient while reducing environmental pollution. • The recycling of solid waste materials offers opportunities for recovery and renewable energy generation. • The recycling of solid waste in water treatment, energy applications, cement production, and fertilizer manufacturing has been discussed. Rapid population expansion has caused an abrupt rise in the amount of solid waste products produced globally. Therefore, there is a pressing demand for strategies for recycling the waste material. There are many different waste categorization principles, including classification based on source, state, or type. This review examines four waste categories using the source of the waste as an indication for classification: agricultural waste, industrial waste, sea material waste, and sludge, all of which constitute solid waste. This review discusses the efficacy of newly developed adsorbents as well as the recovery, regeneration, and subsequent control of used adsorbents through safe reuse. The main objective of this review article is to emphasize the importance and accessibility of inexpensive alternative adsorbents in many applications. It also focuses on energy applications, including fuel cells, supercapacitors, and batteries developed from inexpensive alternative adsorbent-based materials like silica, activated carbon, and ammonia, because these components are crucial for energy use. We provide a summary of the techniques for determining the economicsustainability of solid waste. This review discusses the potential addition of waste materials as cementitious materials in concrete production. It seeks to demonstrate the concept of employing these wastes by describing their engineering, physical, and chemical features. As well as mineral fertilizers, products made from agricultural waste can also be added to the soil to increase its production. These features of waste aid in the remediation of soils. [ABSTRACT FROM AUTHOR]