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The Pd-catalysed direct C–H arylation of thiophene derivatives, appealing for technological application, is performed under green conditions using water as the sole reaction medium. The reaction is independent of the grade of the water, thus enabling the virtuous repurposing of low-purity grade industrial wastewater, allowing one to bring the process to the gram scale and improve its green metrics. [ABSTRACT FROM AUTHOR]

[Display omitted] • A "Turning waste into treasure" strategy was proposed. • An efficient ARM/NiOOH adsorbent has been successfully prepared. • The adsorption kinetics model has been reasonably established. • 348.0 mg g−1 congo red was adsorbed with a ∼ 100 % adsorption efficiency within 5 min. Extracting functional materials from industrial waste residues to absorb organic dyes can maximize waste reuse and minimize water pollution. However, the extraordinarily low purification efficiency still limits the practical application of this strategy. Herein, the lamellar NiOOH is in-situ anchored on the industrial waste red mud surface (ARM/NiOOH) as an adsorbent to purify organic dyes in wastewater. ARM/NiOOH adsorbent with high specific surface area and porosity provides considerable active sites for the congo red (CR), thereby significantly enhancing the removal efficiency of CR. Besides, we fit a reasonable adsorption model for ARM/NiOOH adsorbent and investigate its adsorption kinetics. Resultantly, ARM/NiOOH adsorbent can remarkably adsorb 348.0 mg g−1 CR within 5 min, which is 7.91 times that of raw RM. Our work provides a strategy for reusing industrial waste and purifying sewage pollution, which advances wastewater treatment engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • High sugar, protein of sludge shows outstanding biodrying potential. • Low ventilation rate improved bio-drying cycle and water removal effect. • Revealed the contribution of different water types to water removal. • Lipid degradation role: Crucial for releasing and transforming bound water. • Energy-saving ventilation changes the degradation sequence of organic matter. The effectiveness of dehydration and utilization processes for citric acid dewatered sludge is hampered by its high concentrations of polysaccharides, proteins, and water-binding properties of microbial extracellular polymers (EPS). This research explores the efficacy and mechanisms involved in extracting water from this type of sludge using biological drying technology, with varying rates of ventilation. Especially pertinent was the use of low ventilation rates as control variables. Our results suggest that a scheduled intermittent ventilation at lower rates allows for the most efficient removal of water, achieving a rate of 41.71 % within eight days, according to the zero-order kinetic model. Remarkably, the peak temperature registered was 60 °C, reaching this threshold in just 0.1 days and maintaining high temperatures for approximately 5.9 days. Component analysis of organic matter illustrated a preferential degradation process for lipids under these ventilation conditions which is pivotal for releasing and transforming bound water for efficient extraction, as well as facilitating the breakdown of easily hydrolysable materials. Further, polysaccharide/protein (EPS) decomposition contributed to water removal, though less significantly. The periodic ventilation strategy allowed for the maximum cumulative temperature to be sustained, demonstrating superior efficiency in harnessing bio-generated heat (82.77 % for water evaporation), resulting in dry sludge suitable for self-sustained combustion at relatively low cost ($26.61/t). Highlighted by this study is the considerable potential of energy-efficient ventilation methods in the biological drying treatment of citric acid fermented sludge and similar industrial waste materials. [ABSTRACT FROM AUTHOR]

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]

In this investigation, the modeling of the Aksaray industrial wastewater treatment plant was performed using artificial neural networks with various architectures in the MATLAB software. The dataset utilized in this study was collected from the Aksaray wastewater treatment plant over a 9-month period through daily records. The treatment efficiency of the plants was assessed based on the output values of chemical oxygen demand (COD) output. Principal component analysis (PCA) was applied to furnish input for the Feedforward Backpropagation Artificial Neural Networks (FFBANN). The model's performance was evaluated using the Mean Squared Error (MSE), the Mean Absolute Error (MAE) and correlation coefficient (R2) parameters. The optimal architecture for the neural network model was determined through several trial and error iterations. According to the modeling results, the ANN exhibited a high predictive capability for plant performance, with an R2 reaching up to 0.9997 when comparing the observed and predicted output variables. [ABSTRACT FROM AUTHOR]

The global strategy to reduce waste production implies development of recycling technologies and conversion of various waste into value‐added products. Fly ash is an industrial waste produced in a large amount. It comprised an aluminosilicate cenosphere, which seems perspective as a support for heterogeneous catalysts. Here we report the preparation and application of heterogeneous silver nanocatalysts deposited on cenosphere in the epoxidation reaction, a relevant process for preparation of valuable organic precursors and target chemicals. Reductive wet deposition method yields Ag nano‐dispersed coating of improved quality represented by Ag particles of about 2.7 nm on the surface of the microspheres size of 50–250 microns for catalytic synthesis of styrene‐oxide. The 0.1 mmol/g Ag/cenosphere provided best catalytic results with threefold excess of tret‐butyl hydroperoxide in acetonitrile at 80 °C. Comparison of fly ash cenosphere with other supports suggests that low porosity of microspherical support allows for an easier access of reagents to active sites of the catalyst and significantly increases the yield of epoxide and selectivity of the reaction. [ABSTRACT FROM AUTHOR]

On-site and visual detection of fluorine ions at high selectivity and sensitivity in a water phase is highly anticipated. This work proposes a new mechanism for colorimetric fluorine detection at high selectivity and sensitivity in an aqueous phase based on silicon nanoparticles (SiNPs). The specific silicon corrosion reaction provides the detection with high selectivity and anti-interference properties. The strategy that transforms the role of fluoride ions from reactants into catalysts at elevated temperatures eliminates the concentration requirement of fluoride ions in the silicon corrosion reaction and greatly improves the sensitivity of fluoride ion detection. Under optimal conditions, the limit of detection (LOD) is calculated as 0.11 ppm. Moreover, this strategy enables visual distinguishing of the fluorine content in water samples on the order of ppm, and its comparison with the sewage discharge standard (10 ppm) and the drinking water standard (1 ppm). In a broader context, our approach is likely to enable plausible, convenient and cost-effective fluorine detection in drinking water and industrial waste water. Furthermore, the strategy to transform the role of analytes from reactants into catalysts may shed light on the design of highly sensitive sensing systems based on chemical reactions. [ABSTRACT FROM AUTHOR]

Disposal and harmless utilization of coal-based solid waste, industrial sludge, and other bulk industrial solid waste is a sustainable and economical approach. In this study, coal gangue and printing and dyeing sludge were recycled to reconstruct high-strength ceramsite using a simple and scalable method. The high silica and alumina contents in coal gangue provided a foundation for ceramsite preparation, and the iron oxide in the printing and dyeing sludge could reduce the sintering temperature. The optimal synthesis conditions were as follows: Coal gangue: printing and dyeing sludge = 40:60; sawdust content of 9mass%; sintering temperature of 1175 °C for 15 min; and preheating temperature of 400 °C for 10 min. The designed ceramsite exhibited high compressive strength of 27.26 MPa, low 1-h water absorption of 1.26%, and bulk and apparent densities of 998 and 1597 kg/m3, respectively; thus, it was categorized as high-strength ceramsite. In determining the modelling mechanism during the sintering process, the silicon and aluminum distributions on the ceramsite surface obtained under the optimal preparation conditions was highly consistent, forming a silicoaluminate that supported the ceramsite strength. Sawdust addition increased the pore structure of the ceramsite. The heavy metals contained in the raw materials were well-immobilized in the ceramsite, indicating that the prepared ceramsites were free from secondary contaminants. Use of bulk solid waste to prepare high-strength ceramsites is a feasible resourceful and harmless utilization method, which is of great significance for bulk solid waste disposal and reuse. [Display omitted] • Coal gangue and printing and dyeing sludge were synergistic disposed. • High-strength ceramsite with high performance was prepared. • Preparation conditions for the optimum performance of ceramsites were obtained. • High-strength ceramsite has minimal secondary pollution to the environment. [ABSTRACT FROM AUTHOR]

Heat‐storage materials are important for energy saving to protect the environment. Here, we show a long‐term heat‐storage material based on zirconium‐substituted lambda‐trititanium‐pentoxide (λ‐ZrxTi3−xO5, 0 < x≤0.06). λ‐ZrxTi3−xO5 exhibits a phase transition to zirconium‐substituted beta‐trititanium‐pentoxide (β‐ZrxTi3−xO5) upon application of pressure. The transition pressures were 600 MPa (x=0.04) and about 1 GPa (x=0.06). When the pressure‐produced β‐phase is heated, the β‐phase returns to λ‐phase. The phase transition temperatures (i. e., heat‐storage temperatures) were 185 °C (458 K) and 183 °C (453 K) for x=0.04 and 0.06, respectively. These heat‐storage temperatures are suitable for the reuse of low‐temperature industrial waste heat, which is considered to be a difficult temperature region to be efficiently collected and reused. The present pressure‐sensitive heat‐storage ceramic, which can store the latent heat energy for a prolonged period, is effective for the sustainable reuse of heat energy that are wasted in power plants and industrial factories. [ABSTRACT FROM AUTHOR]

Clay formations are one of the options currently being considered for the storage of radioactive wastes worldwide. In France, the National Radioactive Waste Management Agency (Andra) operates the Meuse/Haute-Marne Underground Research Laboratory in the Callovo-Oxfordian (COx) clay formation to assess the feasibility and safety of an industrial radioactive waste repository. A good level of understanding of the thermo-hydromechanical behaviour of the host rock is paramount for the safety assessment. A new anisotropic elastoplastic damage and viscoplastic model is proposed to describe the hydromechanical behaviour of the COx claystone based on a large dataset of experimental evidence. The model is based on the Hoek and Brown criterion and considers recent findings of the COx hydromechanical behaviour. The key mechanisms considered are: plastic strain hardening prior to reaching the peak strength, a post-peak behaviour characterised by strain softening in the frame of continuum damage mechanics and a residual stage represented by a perfectly plastic behaviour. Time-dependent deformations are also included based on a creep model, which in this work is coupled with damage. The proposed model was implemented with a regularisation scheme based on the non-local implicit gradient in Comsol Multiphysics® with the purpose of performing THM modelling (1D, 2D and 3D) in the framework of the Cigéo project. The numerical implementation is first validated based on several simulations of creep tests at different deviatoric stress and triaxial compression tests at different confining pressures and angles between the loading direction and the bedding, α. Then, the GCS drift hydromechanical behaviour is simulated considering transverse isotropic conditions. It is shown that the model is capable of reproducing the measured peak of pore pressure in sensors near the GCS wall as well as the drift convergence. Importantly, the predicted extent of damaged zones around the drift is consistent with the in situ observations. The impact of damage on the time-dependent behaviour and the permeability was investigated numerically. It was found that the magnitude and anisotropy of drift convergence and the pore pressure drop are sensitive to this coupling and the best agreement was obtained when this effect was taken into account. Finally, the performance of the regularisation scheme is demonstrated with a set of simulations of the drift with different mesh refinements. It is concluded that the proposed model captures the key features of the hydromechanical behaviour of the COx claystone. Highlights: An advanced constitutive model that takes into account the recent findings on the key mechanisms of deformation and failure of COx claystone is proposed. Strain hardening/softening, anisotropic elasticity and plasticity, damage described in the framework of CDM and time-dependent behaviour of COx claystone are considered. The effect of damage and shear fracturation on the transport and viscous properties are also addressed in the model. The model with a regularisation scheme is implemented in Comsol Multiphysics®, which allows several physics to be considered, then to perform 1D, 2D and 3D THMC modellings. The operational nature of the proposed model is successfully evidenced on the GCS drift of the MHM URL, for which the in situ observations are the most challenging to reproduce. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) provide a suitable environment for the interaction of antibiotic resistant bacteria and antibiotic-resistance genes (ARGs) from human, animal, and environmental sources. The aim was to study the influent and effluent of two WWTPs in Croatia to identify bacterial hosts of clinically important beta-lactamase genes (bla TEM, bla VIM, bla OXA-48-like) and observe how their composition changes during the treatment process. A culture-independent epicPCR (Emulsion, Paired isolation and Concatenation Polymerase Chain Reaction) was used to identify the ARG hosts, and 16S rRNA amplicon sequencing to study the entire bacterial community. Different wastewater sources contributed to the significant differences in bacterial composition of the wastewater between the two WWTPs studied. A total of 167 genera were detected by epicPCR, with the Arcobacter genus, in which all ARGs studied were present, dominating in both WWTPs. In addition, the clinically important genera Acinetobacter and Aeromonas contained all ARGs examined. The bla OXA-48-like gene had the highest number of hosts, followed by bla VIM, while bla TEM had the narrowest host range. Based on 16S rRNA gene sequencing, ARG hosts were detected in both abundant and rare taxa. The number of hosts carrying investigated ARGs was reduced by wastewater treatment. EpicPCR provided valuable insights into the bacterial hosts of horizontally transmissible beta-lactamase genes in Croatian wastewater. [ABSTRACT FROM AUTHOR]

An amide‐based covalent organic framework (COF) was successfully synthesized using the reaction between 1,3,5‐trimesoyl chloride and ethylenediamine. The structure and morphology of the COF were characterized using Fourier‐transform infrared spectra, nuclear magnetic resonance spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and Brunauer‐Emmett‐Teller surface area analysis. The COF was employed as a solid‐phase extraction adsorbent for the sampling and preconcentration of chlorophenols from industrial wastewater samples prior to high‐performance liquid chromatography with ultraviolet detection. The experimental parameters influencing the extraction efficiency including type and volume of eluent solvent, sample solution volume, salt concentration, sample flow rate, and sample solution pH were investigated and optimized using a response surface methodology employing Box‐Behnken‐design. Under optimized conditions, calibration curves exhibited good linearities over the range of 0.003–10 µg/mL with determination coefficients (R2) ranging from 0.9982 to 0.9999. The method's limits of detection ranged from 0.001 to 0.01 µg/mL. Good repeatability was achieved with relative standard deviations below 4.7%. The developed procedure utilizing the COF adsorbent was successfully applied to determine chlorophenols accurately and precisely in various industrial wastewater samples. [ABSTRACT FROM AUTHOR]

In-situ modification of cellulose fibers with titania nanoparticles (TiO2 NPs) (TiO2 NPs-cellulose) was carried out via the sol–gel process using titania sol and fibers of cellulose. Cellulose fibers were extracted from wheat straw, an agricultural waste material, whereas titania sol was prepared from titanium(IV) acetoximate, [Ti{ONC(CH3)2}4]. The synthesized TiO2 NPs-cellulose composite was characterized by FT-IR, SEM–EDX, and XRD analyses. The obtained results exposed that TiO2 NPs were homogeneously dispersed over the surface of cellulose fibers. A study was conducted to compare the photocatalytic activities of TiO2 NPs-cellulose composite and TiO2 NPs towards the degradation of methylene blue and methyl orange dyes under sunlight, and it was observed that the photo-degradation of methylene blue (99.99%) and methyl orange (80.73%) within 160 min is higher in the presence of TiO2 NPs-cellulose composite than TiO2 NPs. The adsorption capabilities of TiO2 NPs-cellulose composite towards Pb2+, Cd2+, and Cr3+ toxic metal ions were also examined, and it was found 44.73 mg. g−1 (89.46%), 38.82 mg. g−1 (77.65%), and 4.42 mg. g−1 (8.85%), respectively. Removal of pollutants from textile industrial effluent were also investigated using TiO2 NPs-cellulose composite under sun light. The results obtained were very promising which shows potential of TiO2 NPs-cellulose composite as an efficient photocatalyst and absorbent for real time applications. [ABSTRACT FROM AUTHOR]

In this study, the photocatalytic degradation of phenol, which is commonly found in industrial wastewater at high rates, was investigated using a zinc oxide (ZnO) catalyst. It is thought that our findings will contribute to the removal of phenol in industrial wastewater. The experimental study was conducted in a batch‐type air‐fed cylindrical photocatalytic reactor, and a central composite design (CCD) was chosen and analyzed using response surface methodology (RSM). The study aimed to explore the effects of initial phenol concentration, catalyst concentration, airflow rate, and degradation time on the photocatalytic degradation of phenol and the removal efficiency of total organic carbon (TOC). A quadratic regression model was developed to establish the relationship between phenol degradation, TOC removal effectiveness, and the four factors mentioned. The validity of the model was assessed through an analysis of variance (ANOVA). A good agreement was observed between the model results and the experimental data. As a result of the experiments carried out under optimized conditions, the degradation percentage of phenol was found to be 77.15 %, and the degradation percentage of TOC was 59.87 %. Additionally, pseudo‐first‐order kinetics were used in the photocatalytic degradation of phenol. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a prevalent gram-negative pathogenic bacterium ubiquitous in natural environment. Aquatic environment of wastewater serves as reservoirs of this bacteria and their wide resistance phenomenon to a number of antibiotics is frequently increasing. This study was conducted to determine the prevalence of P. aeruginosa in 10 industrial waste water and 10 tannery waste water samples of whole Dhaka and 65% (13/20) water samples were found positive for P. aeruginosa which was confirmed by both biochemical test & BiologTM Microbial Identification System. Kirby Bauer disc diffusion method was applied for antimicrobial susceptibility testing and isolates showed resistance to most of the commercial antibiotics except neomycin, gentamycin, streptomycin, ciprofloxacin and nalidixic acid, hence confirmed the multidrug resistance (MDR) of P. aeruginosa in wastewater which is one of the life-threatening public health issues all over the world causing ineffectiveness of several antibiotics. So, it is recommended to make sure surface water or food samples not to be contaminated by this antibiotic resistant P. aeruginosa that might be transferred to animal and human. In these circumstances, not only the hygiene practice is the first and foremost prerequisite but also management practices with effective wastewater disposal system can also be a part of awareness. Additionally, appropriate and logical use of antibiotics must be applied to reduce the emergence of multidrug pathogens to environment. [ABSTRACT FROM AUTHOR]

Rare Earth Elements (REEs) are indispensable in contemporary technologies, influencing various aspects of our daily lives and environmental solutions. The escalating demand for REEs has led to increased exploitation, resulting in the generation of diverse REE-bearing solid and liquid wastes. Recognizing the potential of these wastes as secondary sources of REEs, researchers are exploring microbial solutions for their recovery. This mini review provides insights into the utilization of microorganisms, with a particular focus on microalgae, for recovering REEs from sources such as ores, electronic waste, and industrial effluents. The review outlines the principles and distinctions of bioleaching, biosorption, and bioaccumulation, offering a comparative analysis of their potential and limitations. Specific examples of microorganisms demonstrating efficacy in REE recovery are highlighted, accompanied by successful methods, including advanced techniques for enhancing microbial strains to achieve higher REE recovery. Moreover, the review explores the environmental implications of bio-recovery, discussing the potential of these methods to mitigate REE pollution. By emphasizing microalgae as promising biotechnological candidates for REE recovery, this mini review not only presents current advances but also illuminates prospects in sustainable REE resource management and environmental remediation. [ABSTRACT FROM AUTHOR]

The contamination of seafood by heavy metals is a rising health issue in the context of pollution caused by increasing industrialization and urbanization. Crustaceans are particularly susceptible to heavy metal pollution in aquatic ecosystems due to their benthic and sedimentary lifestyle. Here we review crustaceans contamination by heavy metals with a focus on metal sources and dynamics, interaction of metals with other pollutants, metal analysis, bioconcentration and bioaccumulation, toxicity, and strategies to control metals. We observed that crustaceans tend to accumulate more heavy metals than other aquatic animals. Consequently, in certain regions of the world, consuming crustaceans as food may potentially threaten human health. The bioavailability, transport, and interaction of heavy metals with other pollutants depend on various factors, potentially leading to differential toxicity. Heavy metals induce multiple toxic effects on crustaceans, including metabolic dysfunction, genotoxic effects, respiratory impairments, DNA damage, sperm mobility, and quantity, and these poisonous effects will intensify with prolonged exposure time and increasing concentration. The concentration of heavy metals in crustacean samples is usually determined by inductively coupled plasma optical emission spectrometry and mass spectrometry. Approaches to reducing this potential threat include proper industrial wastewater treatment and using low-cost adsorbent materials in aquaculture. [ABSTRACT FROM AUTHOR]

Organic dyes can inflict environmental harm and pose risks to human health, thereby presenting challenges in their treatment within industrial wastewater. Currently, numerous research groups have conducted investigations on the adsorption of organic dyes in industrial wastewater. Herein, this work focuses on the selective adsorption approach towards dyes molecules based on an Anderson-type polyoxometalate (noted as POM-1) as potential adsorbent, which has been functionalized with organic ligands to enhance its negative charge. Adsorption experiments revealed that POM-1 displayed efficient adsorption capabilities towards the cationic dye methyl blue with almost complete adsorption within 25 min, and the adsorption rate was calculated as 98%. A rapid and consecutive filtering experiments have also been performed and further proved the excellent adsorption behavior of POM-1 towards MB. [ABSTRACT FROM AUTHOR]

In the present study, a nanocellulose acetate and acrylate polymer composite membrane was formed by the phase transfer technique. The physical and mechanical properties, water flux, and desalination performance of the achieved composite membrane were investigated. When 3 % (w/w) acrylate polymer, 10 % acetylated nanocellulose, and 0.3 % mass fraction of TiO2 were used for the formation of the membrane, the obtained product could reach a tensile strength of 1.97 N/mm2 and a pure water flux of 51 L/(m2 h). Moreover, the composite membrane achieved a desalination rate of 92.4 %. Thus, the obtained composite membrane could meet the performance requirements for the treatment of industrial wastewater. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in wastewater has been an issue for the environment and human health nowadays. If these wastewaters are exposed directly to the environment, it will be hazardous for the environment and personal health. So, it is very necessary to treat these ground and surface wastewater before exposing into environment. For this, an effective technique were developed which removed heavy metals from wastewater easily, economically and effectively. The cellulose nano-crystals (CNC) were isolated from banana rachis fibres by a series of chemical treatments as well as 50% H2SO4 hydrolysis successively. On the other hand, raw Indonesian type's bituminous coal was collected from Noapara industrial area, Jashore, Khulna and was pyrolysed at 700°C, activated by 2M HCl at 700°C and also carbonised at 500°C followed by activation with 30% H3PO4 acid. In this process, adsorbent of modified charcoal-CNC composites was used for the removal of methyl orange dye and five heavy metals, such as Ni(II), Pb(II), Cr(III), Cd(II) and Co(II)), from wastewater and the uptake capacity, selectivity and removal efficiency were also discussed. The filtering efficiency of wastewater purifications were characterised by FTIR, X-RD, TGA, SEM analysis. Finally, wastewater solution and the filtrates solutions were characterised by UV-Vis, and AAS techniques. [ABSTRACT FROM AUTHOR]

To develop a bioprocess for Cr(VI) detoxification in industrial effluents, a previously isolated potent Cr(VI) reducing haloalkaliphilic Nesterenkonia sp strain NRC-Y was immobilized and investigated for Cr(VI) detoxification. The immobilization matrices included; natural, modified natural, synthetic, and mixtures of natural and synthetic polymers. Among the tested matrices and immobilization approaches, strain NRC-Y cells encapsulated in 1.5% (w/v) amidated pectin beads exhibited the highest Cr(VI) reduction efficiency (47.02% of initial Cr(VI) concentration 150 mg/L after 20 h) followed by alginate (34.4%), alginate-PVA-chitosan (29.6%), alginate-PVA (25.1%), PVA-PVP (23.2%), and PVA (9.5%). Chromate reductase enzyme was poorly immobilized by covalent binding on the tested materials. Therefore, entrapment in amidated pectin was selected for further investigation and immobilization of both whole cells and partially purified chromate reductase. Operational stability study revealed that the immobilized cells were more efficient and stable than the immobilized chromate reductase, and the free cells. For instance, about 60%, 27.0% and 11.5% of these samples initial activities were retained after four successive batches, respectively. The temperature and pH optima for the immobilized cells were 35°C and 7.0, respectively. The pH and thermal stability of strain NRC-Y cells were significantly enhanced upon immobilization in amidated pectin beads by up to 2.3- and 1.4-fold, respectively. The developed immobilized biocatalyst was applied for Cr(VI) reduction in industrial effluent samples, and it completely reduced Cr(VI) within 4 and 8 h for effluents of initial Cr(VI) concentrations 10 and 30 mg/L, respectively. The developed immobilized biocatalyst is promising and has the potential for large-scale Cr(VI) detoxification application. [ABSTRACT FROM AUTHOR]

Il-DyP4, a dye-decolorizing peroxidase (DyP) from Irpex lacteus F17, has a strong ability to oxidise harmful aromatic compounds, implying application potential in the field of environmental protection. However, the low H2O2 stability of Il-DyP4 hinders its practical application. To improve the H2O2 stability of Il-DyP4, oxidation-sensitive amino acids including three Met, one Cys and ten Tyr residues were mutated to less easily oxidizable residues such as Leu, Val and Phe by site-specific mutagenesis. Mutation of the M207 site, located on the surface of the enzyme and far away from the haem group, improved H2O2 stability by 5.3-fold or more. In addition, Y234, also on the enzyme surface, was replaced with Phe and the Y234F mutant displayed 7.3-fold increased H2O2 stability. Furthermore, mutants M207V and Y234F were selected for the decolorization of various types of synthetic dyes, revealing high decolorization activities, especially for M207V with enhanced catalytic activity. The stable DyP mutant M207V has the potential for decolorization of industrial dye wastewater. [ABSTRACT FROM AUTHOR]

We report the effects of sodium phosphate dodecahydrate (Na3PO4·12H2O) as a foam stabilizer on the crystalline phases, microstructure, and properties of foamed glass–ceramics derived from solid industrial wastes. Our findings reveal that Na3PO4·12H2O acts as a pore structure stabilizer, enhancing pore uniformity by releasing P2O5 during decomposition. Additionally, it lowers the softening temperature and viscosity by supplying Na2O. X‐ray diffraction analysis demonstrates that Na3PO4·12H2O does not alter the primary crystal types but does influence the crystallinity and morphology. With an increase in Na3PO4·12H2O content, the porosity and water absorption improve, but the bulk density, thermal conductivity, and compressive strength decrease. The optimal properties are achieved with 4 wt% Na3PO4·12H2O, resulting in significantly higher compressive strength compared to foamed glass–ceramics prepared from other solid wastes. This study provides valuable guidelines for effectively reusing solid industrial wastes to fabricate foamed glass–ceramics. [ABSTRACT FROM AUTHOR]

The release of industrial effluents into fresh water is a major contributor of water contamination. Therefore, it is highly desirable to develop a viable solution to this alarming issue to improve the quality of clean water. To enhance the photocatalytic efficiency and hence utilization ratio of CuO, a series of CuO–FeSe2 composites with different varying contents of FeSe2 were prepared through facile synthetic methods. X-ray diffraction (XRD) and energy-dispersive X-rays (EDX) analysis verified that the samples were successfully prepared without any contaminating phases. The average crystallite sizes of CuO and FeSe2 were computed to be 29 and 21 nm respectively. For the CuO–FeSe2 composites, the crystallite sizes varied between 25 and 27 nm. The morphology of CuO was comprised of needle-shaped structures, whereas that of FeSe2 was observed to be flower-shaped structures comprising of irregular crystals. A red shift in the bandgap of CuO–FeSe2 composites was observed with the increase in FeSe2 concentration. The prepared photocatalysts were utilized to evaluate their efficiency under visible light against Rhodamine B (RhB). Among all the prepared composites, CuO–75% FeSe2 revealed a remarkable performance and degraded 96% RhB in 180 min. Rate constants for the degradation of the dye were determined by applying the Langmuir–Hinshelwood model. [ABSTRACT FROM AUTHOR]

The amine-based cobalt phthalocyanine loaded titanium dioxide nanocomposite (α-nBACoPc/TiO2) was synthesized utilizing a one-pot method. Afterward, a thorough analysis of the nanocomposites' structural and optical properties was conducted. The crystalline character of the composite is shown by X-ray powder diffraction. The successful synthesis of α-nBACoPc/TiO2 nanomaterials was validated by infrared spectroscopy. The samples' optical studies reveal a gradual diminution of the composites' optical band gap. Nanocomposites were used in the degradation of synthetic dyes (rhodamine B), and it was discovered that after 150 min of simulating sunlight exposure, the composite α-nBACoPc/TiO2 (2:100) exhibited the best degradation; about 90% of the organic material had been broken down. This may be due to the synergistic action of α-nBACoPc and TiO2, which significantly increases the efficiency of light utilization. The ideal properties of positive catalytic activity of the central ion and high specific surface area of the composite accelerate charge transport and reduce charge complexation. Cycling experiments have demonstrated the good stability of the nanocomposite. The potential of nanocomposites (α-nBACoPc/TiO2) in the area of industrial waste dye degradation is thus confirmed by this investigation. [ABSTRACT FROM AUTHOR]

The current study presents a pioneering approach to industrial effluent treatment by harnessing cavitation-based hybrid methods for treatment of two different bio-refractory real effluents from polymer processing industry for the first time. Laboratory-scale optimization tailored for distinct effluents using acoustic cavitation (AC) revealed the optimum operating parameters as 120W as ultrasonic power, pH of 7, a 70% duty cycle and a 120-min treatment duration. By incorporating oxidants, the AC + O3 + H2O2 approach achieved impressive chemical oxygen demand (COD) reduction of 56.45% and 63.19% for Effluent-1 and Effluent-2, respectively, outperforming alternative methods. Additionally, the utilization of hydrodynamic cavitation in the combined approach (HC + O3 + H2O2 approach) resulted in COD reductions of 62.16% for Effluent-1 and 66.37% for Effluent-2, highlighting the potential for process intensification and commercial utilization. Overall, the effective approach for the treatment of polymer processing industrial effluent utilizing cavitation combined with other AOPs has been demonstrated. [ABSTRACT FROM AUTHOR]

In this work, we explored the adsorptive detoxification potential of titania–bentonite clay composite for removing a cationic dye (crystal violet) from aqueous medium. Fresh clay composite sample were prepared by impregnated method, followed by spectroscopic characterization by SEM, FTIR, and EDX. After that, in batch studies dye removal were examined. The results under optimum conditions showed that this composite material has a 96% elimination capacity. Maximum removal of crystal violet was 49.26 mg/g, following Pseudo-second order kinetic model occurred at pH 8, at 125 rpm and 25 ppm initial concentration at 45 °C. Kinetics of reactions and isotherm models were investigated. Adsorption data showing the presence of monolayer adsorption were fitted using the Langmuir isotherm model. Chemisorption was shown to prevail according to Temkin isotherm criteria. Pseudo-second-order kinetics was followed in this case. For removing dye from industrial effluents, this titania–bentonite composite serves as a nonbiodegradable, low-cost, reliable, and ecologically safe adsorbent. [ABSTRACT FROM AUTHOR]

This study focuses on the industrial wastewater discharge of 27 cities in the Yangtze River Delta urban agglomeration. It selects five water pollutant indicators from industrial wastewater discharge, including chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), petroleum pollutants (PP), and major heavy metal content (HM). A shadow price model for industrial wastewater discharge pollutants in each city of the Yangtze River Delta urban agglomeration is constructed, and empirical research is conducted using government-provided statistical data. The study reveals that the economic losses associated with industrial wastewater discharge in the 27 cities of the Yangtze River Delta urban agglomeration range from 5.9296 billion to 6.448 billion yuan. Shanghai demonstrates the highest economic losses caused by industrial wastewater discharge, surpassing 0.45 billion yuan annually. In contrast, Anqing city experiences the lowest economic losses, approximately ranging from 93 million to 104 million yuan per year due to industrial wastewater discharge. [ABSTRACT FROM AUTHOR]

Confronted with the fast social development, the speed of garbage generation has increased. Therefore, from every aspect, especially staying green and healthy, it is urgent and vital to ensure accurate and stable garbage classification. In the field of garbage classification, household garbage has a large volume and the classification process still requires manual intervention. Besides, most of the current studies focus on industrial waste and medical waste, while the existing studies on household garbage are not effective enough. Furthermore, these studies are mostly trained and validated in self-built datasets, making the experimental results insufficiently representative and severely limiting the development of research. Aiming to facilitate the study of household garbage classification, this paper proposes a simple yet effective network model (FConvNet) to improve classification performance. In this paper, an effective convolution block with fused convolution is designed to enhance the potential correlation of the features in the spatial dimension, and then a lightweight symmetric structure is constructed to infer more information about the feature representation. The experiments on public datasets have justified the effectiveness of FConvNet with accuracy rates of 95%, 95% and 97%, achieving better performance on public datasets compared to baselines. Additionally, an online system based on the WeChat mini program framework is designed to provide convenient household garbage classification services and enable the collection of uploaded images to perform model optimizations. [ABSTRACT FROM AUTHOR]

Aluminum can be found in water and vegetables in the form of the trivalent ion (Al3+), which can potentially contaminate food and water. Overconsumption of aluminum can lead to serious health problems in humans. Therefore, there is a need for an economical and simple procedure to detect the presence of aluminum. In this study, we synthesized a conjugate of Grewia asiatica extract with silver nanoparticles. The nanoparticle-stabilized fruit extract of Grewia asiatica was found to be an extremely selective sensor of Al3+ in tap water, DI water, industrial wastewater, and human blood plasma. We characterized the Grewia asiatica-conjugated silver nanoparticles (GA-AgNPs) using UV-visible, SEM, and AFM techniques and found that they were stable in an extensive pH range and different electrolyte concentrations up to 10 M NaCl. The GA-AgNPs were circular in shape with typical particle sizes of 65–97 nm. We inspected the photo physical properties of GA-AgNPs concerning metallic ions using UV-visible spectroscopy and found that they were highly selective for Al3+ ions, with no interfering ions detected in competitive experimentation. The absorption intensity of GA-AgNPs was directly related to Al3+ concentration over a wide range of concentrations (6.25–500 μM). Jobs plot experiment displayed 1 : 1 binding stoichiometry between GA-AgNPs, and Al3+. Additionally, GA-AgNPs were effectively utilized for the recognition of Al3+ in laboratory tap water, DI water, industrial wastewater, and human blood plasma. [ABSTRACT FROM AUTHOR]

In this study, biohydrogen was produced by R. johrii strain VT1 using an anaerobic photo-fermentation process on low-cost industrial wastewater and then used for nitrate reduction in the presence of a chemical catalyst. The effect of substrate, light intensity, and pH on biohydrogen production was investigated. For efficient nitrate reduction, a Pd–Cu/alumina bimetallic catalyst was prepared and analyzed by XRD, FTIR, FESEM, and ICP. Accumulative biohydrogen production was 284.67 ml/h (0.409 ± 0.005 mol/m3h), with molasses, a light intensity of 5300 lux, and a pH of 9. Nitrate removal efficiency was 81.70%, and nitrogen selectivity was 94.25%. The XRD results also showed the stability of the catalyst structure during the reduction. Our study shows that this combined method is effective for nitrate removal and has the potential for large-scale work because of the affordable and sustainable green hydrogen production from wastewater. This is the first report of using biological hydrogen for harmful nitrate removal from drinking water in the presence of a chemical catalyst. [Display omitted] • R,johrii, produced biohydrogen with industrial wastes, as available and affordable substrate, efficiently. • This is the first report of the use of biohydrogen for nitrate reduction through chemical catalysts. • Pd–Cu//γ-Al 2 O 3 , used as an efficient and selective catalyst for nitrate removal from waters. [ABSTRACT FROM AUTHOR]

The noble metals, owing to their unique properties, find extensive applications in various modern industries. However, as non-renewable resources, the reserves of noble metals in the natural environment are limited. Therefore, recovering noble metals from discarded industrial waste not only helps alleviate the challenges of noble metal resource scarcity, but also addresses environmental pollution. Herein, the state-of-the-art techniques for noble metal recovery are divided into two categories, pyrometallurgy and hydrometallurgy, in which the conversion mechanisms are discussed. The pyrometallurgy strategies depend primarily on high-temperature smelting reduction, while the hydrometallurgy strategies are segmented into leaching, enrichment and extraction, showing enormous development potential in the future. The novel exploration of noble metal pyrometallurgical extraction is briefly reviewed. The solvolysis, photochemistry, and electrochemistry-initiated approaches for noble metal recycling from secondary resource are summarized in detail. Finally, the future challenges and development prospects of sustainable noble metal recovery are discussed. This work offers a summary of current recovery methods for noble metals and provides a reference for resource utilization. [ABSTRACT FROM AUTHOR]

AbstractThe objective of the study is to determine the effects of different fibre types and ratios on the mechanical and physical properties of alkali-activated concrete (AAC) and to optimise important properties such as workability, unit weight, water absorption, compressive strength, modulus of elasticity and abrasion resistance of these concretes. Concrete samples were produced using steel and polyester fibres at ratios of 0.25%, 0.50%, 0.75% and 1%. The fibre ratios were varied, and various tests were conducted to determine the mechanical and physical properties of the concrete samples. The experiments clearly revealed the effects of fibre types and ratios on the performance of concrete. These results clearly demonstrate the effects of different fibre types and ratios on the mechanical and physical properties of AACs. Particularly noteworthy is the water-retaining property of polyester fibres, their effect on workability and their enhancing effect on abrasion resistance. The effects of steel fibres on compressive strength and modulus of elasticity are more pronounced, but they may present disadvantages in terms of workability and abrasion resistance. It is observed that mixed fibre usage provides a good balance in some properties. This study provides a roadmap for evaluating sustainable material options in the concrete industry and guiding future research. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) is a type of polymer, which exists in various forms in the environment. Very few studies are available concerning the structure or enzymatic mechanism of the microbial community, which can degrade PU. Degradation of PU remains a difficult problem with respect to the environmental and biological disciplines. This study mainly focused on identifying the micro-organisms able to degrade polyurethane and confirming the degradation by performing a plate assay, Sturm test and scanning electron microscopy. Optimal culture conditions for maximum PU degradation were also analyzed through classical methods. A soil burial test was conducted by placing polyurethane films in the soil for one month, and the microbe growing on the surface of polyurethane films—with a maximum degradation of 55%—was isolated and identified as Aspergillus versicolor (ARF5). The culture medium was also optimized with different physical and chemical parameters for maximum PU degradation. The presence of CO2 as a by-product of PU biodegradation was confirmed through the Sturm test. [ABSTRACT FROM AUTHOR]

We have developed an innovative thin-film nanocomposite membrane that contains cellulose acetate (CA) with small amounts of TiO2-decorated graphene oxide (GO) (ranging from 0.5 wt.% to 2 wt.%) sandwiched between two polytetrafluoroethylene (PTFE)-like thin films. The PTFE-like films succeeded in maintaining the bulk porosity of the support while increasing the thermal and chemical robustness of the membrane and boosting the catalytic activity of TiO2 nanoparticles. The membranes exhibited a specific chemical composition and bonding, with predominant carbon–oxygen bonds from CA and GO in the bulk, and carbon–fluorine bonds on their PTFE-like coated sides. We have also tested the membranes' photocatalytic activities on azithromycin-containing wastewaters, demonstrating excellent efficiency with more than 80% degradation for 2 wt.% TiO2-decorated GO in the CA-GO-TiO2/PTFE-like membranes. The degradation of the azithromycin formulation occurs in two steps, with reaction rates being correlated to the amount of GO-TiO2 in the membranes. [ABSTRACT FROM AUTHOR]

Red mud (RM) is an industrial waste generated in the process of aluminum refinement. The recycling and reusing of RM have become urgent problems to be solved. To explore the feasibility of using RM in geotechnical engineering, this study combined magnesium oxide (MgO) (or calcium oxide (CaO)) with RM as an RM-based binder, which was then used to stabilize the soil. The physical, mechanical, and micro-structural properties of the stabilized soil were investigated. As the content of MgO or CaO in the mixture increased, the unconfined compressive strength (UCS) of the RM-based cementitious materials first increased and then decreased. For the soils stabilized with RM–MgO or RM–CaO, the UCS increased and then decreased, reaching a maximum at RM:MgO = 5:5 or RM:CaO = 8:2. The addition of sodium hydroxide (NaOH) promoted the hydration reaction. The UCS enhancement ranged from 8.09% to 66.67% for the RM–MgO stabilized soils and 204.6% to 346.6% for the RM–CaO stabilized soils. The optimum ratio of the RM–MgO stabilized soil (with NaOH) was 2:8, while that of the RM–CaO stabilized soil (with NaOH) was 4:6. Freeze–thaw cycles reduced the UCS of the stabilized soil, but the resistance of the stabilized soil to freeze–thaw erosion was significantly improved by the addition of RM–MgO or RM–CaO, and the soil stabilized with RM–MgO had better freeze–thaw resistance than that with RM–CaO. The hydrated magnesium silicate generated by the RM–MgO stabilized soil and the hydrated calcium silicate generated by the RM–CaO stabilized soil helped to improve the UCS of the stabilized soil. The freeze–thaw cycles did not weaken the formation of hydration products in the stabilized soil but could result in physical damage to the stabilized soils. The decrease in the UCS of the stabilized soil was mainly due to physical damage. [ABSTRACT FROM AUTHOR]

Some composite materials have been prepared, constituted by a cyclodextrin-bis-urethane-based nanosponge matrix in which a reduced graphene oxide/silver nanoparticles photocatalyst has been dispersed. Different chain extenders were employed for designing the nanosponge supports, in such a way as to decorate their hyper-cross-linked structure with diverse functionalities. Moreover, two different strategies were explored to accomplish the silver loading. The obtained systems were successfully tested as catalysts for the photodegradation of emerging pollutants such as model dyes and drugs. Enhancement of the photoactive species performance (up to nine times), due to the synergistic local concentration effect exerted by the nanosponge, could be assessed. Overall, the best performances were shown by polyamine-decorated materials, which were able to promote the degradation of some particularly resistant drugs. Some methodological issues pertaining to data collection are also addressed. [ABSTRACT FROM AUTHOR]

Waste management is one of the many major challenges faced by all urban cities around the world. With the increase in population, the current mechanisms for waste collection and disposal are under strain. The waste management problem is a global challenge that requires a collaborative effort from different stakeholders. Moreover, there is a need to develop technology-based solutions besides engaging the communities and establishing novel policies. While there are several challenges in waste management, the collection of waste using the current infrastructure is among the top challenges. Waste management suffers from issues such as a limited number of collection trucks, different types of household and industrial waste, and a low number of dumping points. The focus of this paper is on utilizing the available waste collection transportation capacity to efficiently dispose of the waste in a time-efficient manner while maximizing toxic waste disposal. A novel knapsack-based technique is proposed that fills the collection trucks with waste bins from different geographic locations by taking into account the amount of waste and toxicity in the bins using IoT sensors. Using the Knapsack technique, the collection trucks are loaded with waste bins up to their carrying capacity while maximizing their toxicity. The proposed model was implemented in MATLAB, and detailed simulation results show that the proposed technique outperforms other waste collection approaches. In particular, the amount of high-priority toxic waste collection was improved up to 47% using the proposed technique. Furthermore, the number of waste collection visits is reduced in the proposed scheme as compared to the conventional method, resulting in the recovery of the equipment cost in less than a year. [ABSTRACT FROM AUTHOR]

Whether the oilfield sewage index can reach the reinjection specification is a crucial issue that is urgently need to be solved in polymer flooding systems. Thus the coagulability and floc morphology development of dual coagulants was systematically studied in different pH oily wastewaters. Acidification improved the deprotonation ability of coagulant. Hydrophobic associative polyaluminum silicate-poly dimethyl diallyl ammonium chloride (PASSC-PD) resolved the problem of excessive acid addition. The dual coagulants prepared not only preserved the high charge density of polyaluminum silicate (PASS) itself but also made it have the hydrophobic association and strong bridging ability. Besides, PASSC-PD was compared with hydrophobic associative polyaluminum silicate (PASS-C), PASS, and poly dimethyl diallyl ammonium chloride (PDMDAAC) pertaining to the polymer flooding oily sewage of Daqing Oilfield. The coagulation result demonstrated that PASSC-PD exhibited more advantageous turbidity and oil removal efficiencies than PASS-C, PASS, and PDMDAAC. The floc morphology result showed that adding dual coagulant made the petal-like floc of oily sewage larger at the pH value of 6. Furthermore relevant results evidenced that the coagulant had more successful fruits of turbidity removal of 96.5% and oil removal of 96.3% under weak acid conditions. These can satisfy the reinjection condition of oily sewage. [ABSTRACT FROM AUTHOR]

The high-temperature composite phase change materials (HCPCMs) were prepared from solid waste blast furnace slag (BFS) and NaCl-KCl binary eutectic salt to achieve efficient and cost-effective utilization. To ensure good chemical compatibility with chlorine salt, modifier fly ash (FA) was incorporated and subjected to high-temperature treatment for the processing of industrial solid waste BFS, which possesses a complex chemical composition. The HCPCMs were synthesized through a three-step process involving static melting, solid waste modification, and mixing–cold pressing–sintering. Then, the influence of the modification method and the amount of SiC thermal conductivity reinforced material on chemical compatibility and thermodynamic performance was explored. The results demonstrate that the predominant phase of the modified solid waste is Ca2Al2SiO7, which exhibits excellent chemical compatibility with chlorine salt. HCPCMs containing less than 50 wt.% chloride content exhibit good morphological stability without any cracks, with a melting temperature of 661.76 °C and an enthalpy value of 108.73 J/g. Even after undergoing 60 thermal cycles, they maintain good chemical compatibility, with leakage rates for melting and solidification enthalpies being only 6.3% and 0.23%, respectively. The equilibrium was achieved when 40 wt.% of chloride salt was encapsulated upon the addition of 10% of SiC, and the incorporation of SiC resulted in an enhancement of thermal conductivity for HCPCMs to 2.959 W/(m·K) at room temperature and 2.400 W/(m·K) at 200 °C, with an average increase of about 2 times. The cost of the prepared HCPCMs experienced a significant reduction of 81.3%, demonstrating favorable economic performance and promising prospects for application. The research findings presented in this article can offer significant insights into the efficient utilization of solid waste. [ABSTRACT FROM AUTHOR]