Buffer-free ozone-ferrate(VI) systems for enhanced oxidation of electron-deficient contaminants: Synergistic enhancement effects, systematic toxicity assessment, and practical applications.

The combination of ozone (O3) and ferrate (Fe(VI)) oxidation technology demonstrates substantial potential for practical applications, though it has been underreported, resulting in gaps in comprehensive activity assessments and thorough exploration of its mechanisms. This study reveals that the previous use of a borate buffer solution obscured certain synergistic reactions between O3 and Fe(VI), causing a reduction of activity by ∼40 % when oxidizing the electron-deficient pollutant atrazine. Consequently, we reassessed the activity and mechanisms using a buffer-salt-free O3/Fe(VI) system. Our findings showed that the hydroxyl radical (·OH) served as the predominant active species, responsible for an impressive 95.9 % of the oxidation activity against electron-deficient pollutants. Additional experiments demonstrated that the rapid production of neglected and really important superoxide radicals (·O2-) could facilitate the decomposition of O3 to generate ·OH and accelerate the reduction of Fe(VI) to Fe(V), reactivating O3 to produce ·OH anew. Intriguingly, as the reaction progressed, the initially depleted Fe(VI) was partially regenerated, stabilizing at over 50 %, highlighting the significant potential of this combined system. Moreover, this combined system could achieve a high mineralization efficiency of 80.4 % in treating actual coking wastewater, complemented by extensive toxicity assessments using Escherichia coli, wheat seeds, and zebrafish embryos, showcasing its robust application potential. This study revisits and amends previous research on the O3/Fe(VI) system, providing new insights into its activity and synergistic mechanisms. Such a combined technology has potential for the treatment of difficult-to-degrade industrial wastewater.

Nanoconfined Fe(II) releaser for long-term arsenic immobilization and its sustainability assessment.

Ferrous (Fe(II))-based oxygen activation for pollutant abatements in soil and groundwater has attracted great attention, while the low utilization and insufficient longevity of electron donors are the primary challenges to hinder its practical applications. Herein, we propose a nanoconfined Fe(II) releasing strategy that enables stable long-term electron donation for oxygen activation and efficient arsenic (As) immobilization under oxic conditions, by encapsulating zero-valent iron in biomass-derived carbon shell (ZVI@porous carbon composites; ZVI@PC). This strategy effectively enhances the generation of reactive oxygen species, enabling efficient oxidation and subsequent immobilization of As(III) in soils. Importantly, this Fe(II) releaser exhibits strong anti-interference capability against complex soil matrices, and the accompanying generation of Fe(III) enables As immobilization in soils, effectively lowering soil As bioavailability. Soil fixed-bed column experiments demonstrate a 79.5 % reduction of the total As in effluent with a simulated rainfall input for 10 years, indicating the excellent long-term stability for As immobilization in soil. Life cycle assessment results show that this Fe(II) releaser can substantially mitigate the negative environmental impacts. This work offers new insights into developing green and sustainable technologies for environmental remediation.

Highly efficient treatment of tetracycline using coupled electro-Fenton and electrocoagulation process: Mechanism and toxicity assessment.

In this study, a novel carbon fiber brush (CFB) electrode was designed using carbon fiber filaments and conductive metals. It was used as the cathode to construct an efficient coupled electro-Fenton and electrocoagulation (EF-EC) process for tetracycline (TC) treatment. An optimal 97.9% removal rate of 10 mg L-1 TC was achieved within 20 min. The coupled process is less pH-dependent and more effective in treating TC compared to the traditional individual electro-Fenton (EF) or electrocoagulation (EC) process, achieving efficient TC removal under neutral pH conditions. The removal rate of 10 mg L-1 TC consistently remained above 92% at 20 min after ten cycle experiments using the same electrodes in a Fe-CFB system (92.7-97.9%), indicating excellent reusability and stability of the CFB cathode. Mechanism analysis showed both EF and EC processes were involved in the system. Radicals (such as •OH and SO4-•) generated by EF contributed to the degradation of TC, yielding nine intermediates. Coagulants (such as Fe(OH)3) generated by EC contributed to the removal of TC. Toxicity prediction results indicated that over half of the nine intermediates exhibited lower biotoxicity compared to TC. This study provides a feasible alternative cathode for the efficient treatment of TC using EF-EC process.

Removal enhancement of persistent basic fuchsin dye from wastewater using an eco-friendly, cost-effective Fenton process with sodium percarbonate and waste iron catalyst.

In this comprehensive investigation, we evaluate the efficacy of the Fenton process in degrading basic fuchsin (BF), a resistant dye. Our primary focus is on the utilization of readily available, environmentally benign, and cost-effective reagents for the degradation process. Furthermore, we delve into various operational parameters, including the quantity of sodium percarbonate (SPC), pH levels, and the dimensions of waste iron bars, to optimize the treatment efficiency. In the course of our research, we employed an initial SPC concentration of 0.5 mM, a pH level of 3, a waste iron bar measuring 3.5 cm in length and 0.4 cm in diameter, and a processing time of 10 min. Our findings reveal the successful elimination of the BF dye, even when subjected to treatment with diverse salts and surfactants under elevated temperatures and acidic conditions (pH below 3). This underscores the robustness of the Fenton process in purifying wastewater contaminated with dye compounds. The outcomes of our study not only demonstrate the efficiency of the Fenton process but highlight its adaptability to address dye contamination challenges across various industries. Critically, this research pioneers the application of waste iron bars as a source of iron in the Fenton reaction, introducing a novel, sustainable approach that enhances the environmental and economic viability of the process. This innovative use of recycled materials as catalysts represents a significant advancement in sustainable chemical engineering practices.

Green low-cost synthesis of zero-valent iron nanoparticles from Palm Petiole Extract for Cr(VI) removal from water.

One of the hottest research topics over the last decades was the valorization or/and recycling of agro-industrial wastes into different valuable liquid or solid products, which is considered a sustainable and low-cost approach. In this study, we developed zero-valent iron nanoparticles from Palm Petiole Extract (P-NZVI) using a green and straightforward approach. The as-synthesized P-NZVI was used to adsorb Cr(VI) in water. The physico-chemical characterizations of P-NZVI, including the particle size, crystalline structure, surface area, morphology, and functional groups, were investigated via several techniques such as UV-vis spectroscopy, SEM, TEM, XRD, FTIR, AFM, DLS, pHZPC measurement, and BET analysis. The adsorption performance of P-NZVI was studied under different operational parameters, including pollutant concentration, pH, temperature, and adsorbent mass. The adsorption rate was found to be 89.3% within 40 min, corresponding to the adsorption capacity of 44.47 mg/g under the following conditions: initial Cr(VI) concentration of 40 mg/L, pH 5, and a P-NZVI dosage of 1 g/L. It was found that the adsorption pattern follows the Langmuir and the pseudo-second-order kinetic models, indicating a combination of monolayer adsorption and chemisorption mechanisms. The thermodynamic study shows that the adsorption process is endothermic and spontaneous. The reusability of P-NZVI was carried out four times, showing a slight decrease from 89.3 to 87%. These findings highlight that P-NZVI's could be an effective green adsorbent for removing Cr(VI) or other types of toxic pollutants from water.

Effective immobilization and biosafety assessment of antimony in soil with zeolite-supported nanoscale zero-valent iron.

Antimony (Sb) contamination in certain areas caused by activities such as antimony mining and smelting poses significant risks to human health and ecosystems. In this study, a stable composite material consisting of natural zeolite-supported nanoscale zero-valent iron (Z-ZVI) was successfully prepared. The immobilization effect of Z-ZVI on Sb in contaminated soil was investigated. Experimental results showed that Z-ZVI exhibited superior performance compared to pure nano zero-valent iron (nZVI) in terms of stability, with a lower zeta potential (-25.16 mV) at a pH of 7 and a higher specific surface area (54.54 m2/g). It can be easily applied and dispersed in contaminated soils. Additionally, Z-ZVI demonstrated a more abundant porous structure. After 60 days of treatment with 3% Z-ZVI, the leaching concentration of Sb in the contaminated soil decreased from 1.32 mg/L to 0.31 mg/L (a reduction of 76%), and the concentration of available Sb species decreased from 19.84 mg/kg to 0.71 mg/kg, achieving a fixation efficiency of up to 90%. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis confirmed the effective immobilization of Sb in the soil through reduction of antimonate to antimonite, precipitation, and adsorption processes facilitated by Z-ZVI. Moreover, the addition of Z-ZVI effectively reduced the bioavailability of Sb in the contaminated soil, thereby mitigating its toxicity to earthworms. In conclusion, Z-ZVI can be utilized as a promising material for the safe remediation and antimony and other heavy metal-contaminated soils.

Z-scheme heterojunction composed of Fe-doped g-C3N4 and Bi2MoO6 for photo-fenton degradation of antibiotics over a wide pH range: Activity and toxicity assessment.

In photo-Fenton technology, the narrower pH range limits its practical application for antibiotic wastewater remediation. Therefore, in this study, a Z-scheme heterojunction photo-Fenton catalyst was constructed by Fe-doped graphite-phase carbon nitride in combination with bismuth molybdate for the degradation of typical antibiotics. Fe doping can shorten the band gap and increase visible-light absorption. Simultaneously, the constructed Z-scheme heterojunction provides a better charge transfer pathway for the photo-Fenton reaction. Within 30 min, Fe3CN/BMO-3 removed 95.54% of tetracycline hydrochloride (TC), and its remarkable performance was the higher Fe3+/Fe2+ conversion efficiency through the decomposition of H2O2. The Fe3CN/BMO-3 catalyst showed remarkable photo-Fenton degradation performance in a wide pH range (3.0-11.0), and it also had good stability in the treatment of TC wastewater. Furthermore, the order of action of the active species was h+ > ·O2- > 1O2 > ·OH, and the toxicity assessment suggested that Fe3CN/BMO-3 was effective in reducing the biotoxicity of TC. The catalyst proved to be an economically feasible and applicable material for antibiotic photo-Fenton degradation, and this study provides another perspective on the application of elemental doping and constructed heterojunction photo-Fenton technology for antibiotic water environmental remediation.

Valorisation of metallurgical residues via carbothermal reduction: A circular economy approach in the cement and iron and steel industry.

The decarbonisation of the steel and cement industry is of utmost importance in tackling climate change. Hence, steel production in modern integrated steel mills will be shifted towards electric arc furnaces in the future, in turn causing dwindling supplies of blast furnace slag, which is used as a supplementary cementitious material inter alia to reduce the CO2 emissions of cement production. Achieving a sustainable circular steel and building material economy requires the valorisation of currently landfilled steel slags and investigating utilisation options for electric arc furnace slag, which is increasingly being generated. For this purpose, different metallurgical residues and by-products were treated by carbothermal reduction in an inductively heated graphite crucible and then rapidly cooled by wet granulation, yielding a slag fraction similar to granulated blast furnace slag and a metal fraction valuable as a secondary raw material. A spreadsheet-based model was developed to calculate residue combinations to accomplish target compositions of the slag and metal fractions to fulfil previously identified requirements of the targeted cementitious and ferrous products. The results demonstrate the high accuracy of the model in predicting the properties (e.g. main oxide composition) of the generated slag and metal fraction, which fulfil the needed requirements for their use as (i) a supplementary cementitious material and (ii) a secondary raw material in steel production.

Chromium immobilization from wastewater via iron-modified hydrochar: Different iron fabricants and practicality assessment.

The recycling of industrial solid by-products such as red mud (RM) has become an urgent priority, due to their large quantities and lack of reutilization methods can lead to resource wastage. In this work, RM was employed to fabricate green hydrochar (HC) to prepare zero-valent iron (ZVI) modified carbonous materials, and conventional iron salts (IS, FeCl3) was applied as comparison, fabricated HC labeled as RM/HC and IS/HC, respectively. The physicochemical properties of these HC were comprehensively characterized. Further, hexavalent chromium (Cr(VI)) removal performance was assessed (375.66 and 337.19 mg/g for RM/HC and IS/HC, respectively). The influence of dosage and initial pH were evaluated, while isotherms, kinetics, and thermodynamics analysis were also conducted, to mimic the surface interactions. The stability and recyclability of adsorbents also verified, while the practical feasibility was assessed by bok choy-planting experiment. This work revealed that RM can be used as a high value and green fabricant for HC the effective removal of chromium contaminants from the wastewater.

Iron-lanthanum supported on graphite sheets for As(III) removal from aqueous solution: kinetics, thermodynamic and ecotoxicity assessment.

Graphene-based material is widely used to remove arsenic from water due to its layered structure with high surface area. Here, we have successfully synthesized Fe-La bimetallic modified graphite sheet materials to more efficiently remove As(III) from aqueous solution. The results showed that Fe-La-graphite sheets (FL-graphite sheets) have a larger specific surface area (194.28 m2·g-1) than graphite sheets (2.80 m2·g-1). The adsorption capacity of FL-graphite sheets for As(III) was 51.69 mg·g-1, which was higher than that of graphite sheets (21.91 mg·g-1), La-graphite sheets (26.06 mg·g-1), and Fe-graphite sheets (40.26 mg·g-1). The FL-graphite sheets conformed to the Freundlich and Dubinin-Radushkevich isotherm, and the maximum adsorption capacity was 53.62 mg·g-1. The removal process obeys intra-particle diffusion and pore diffusion for As(III). The results of batch adsorption experiments and characterization analyses demonstrated that oxidation, ligand exchange, and inner sphere complexation mechanisms involved in the adsorption of FL-graphite sheets to As(III) in comparison with graphite sheets. In addition, electrostatic attraction mechanism was found vital in the adsorption. Ecotoxicity assessment revealed that FL-graphite sheets have little influence on rice germination and growth, but reduced the toxicity of As(III) to rice. Therefore, the FL-graphite sheets have good practical application value in purifying As(III) polluted water with litter ecotoxicity.

Smart Design of ZnFe and ZnFe@Fe Nanoparticles for MRI-Tracked Magnetic Hyperthermia Therapy: Challenging Classical Theories of Nanoparticles Growth and Nanomagnetism.

Iron Oxide Nanoparticles (IONPs) hold the potential to exert significant influence on fighting cancer through their theranostics capabilities as contrast agents (CAs) for magnetic resonance imaging (MRI) and as mediators for magnetic hyperthermia (MH). In addition, these capabilities can be improved by doping IONPs with other elements. In this work, the synthesis and characterization of single-core and alloy ZnFe novel magnetic nanoparticles (MNPs), with improved magnetic properties and more efficient magnetic-to-heat conversion, are reported. Remarkably, the results challenge classical nucleation and growth theories, which cannot fully predict the final size/shape of these nanoparticles and, consequently, their magnetic properties, implying the need for further studies to better understand the nanomagnetism phenomenon. On the other hand, leveraging the enhanced properties of these new NPs, successful tumor therapy by MH is achieved following their intravenous administration and tumor accumulation via the enhanced permeability and retention (EPR) effect. Notably, these results are obtained using a single low dose of MNPs and a single exposure to clinically suitable alternating magnetic fields (AMF). Therefore, as far as the authors are aware, for the first time, the successful application of intravenously administered MNPs for MRI-tracked MH tumor therapy in passively targeted tumor xenografts using clinically suitable conditions is demonstrated.

Adsorptive removal of dissolved Iron from groundwater by brown coal - A low-cost adsorbent.

Iron (Fe) contamination in groundwater is a widespread issue, necessitating the implementation of efficient removal methods to ensure the provision of safe drinking water. To contribute to the development of effective and sustainable solutions for addressing Fe contamination problems, this study investigated the potential of natural brown coal (BC) as a cost-effective adsorbent for removing dissolved Fe from groundwater. The study also explored the regeneration and reusability potential, as well as the effects of operational parameters, including pH, temperature, adsorbate concentration, and competitive ions, on the adsorption process. The equilibrium data fitted very well with the Langmuir model (R2 = 0.983), yielding a maximum adsorption capacity of 1.41 mg g-1. The adsorption kinetics were well described by the pseudo-second-order kinetic model. Notably, higher solution pH, Fe concentration, and temperature values led to higher Fe removal. The adsorption process exhibited endothermic behaviour, accompanied by an increase in randomness at the interface between the BC and the Fe. The BC was easily regenerated and maintained good adsorption capacity after four cycles of adsorption and regeneration. However, the presence of high-valent cations could affect its performance. Fourier-transform infrared spectrometry, coupled with structural and aqueous solution elemental analyses, revealed a synergetic adsorption mechanism, comprising ion-exchange with mono and divalent basic cations and complexation with functional groups. Overall, these findings highlight the potential of brown coal as a cost-effective adsorbent for Fe removal from groundwater.

Phosphate removal by low-cost industrial byproduct iron shavings: Efficacy and longevity.

Iron shavings (IS) are low-cost industrial byproducts that show great potential in removing phosphorus (P) from contaminated water. This work investigates the effectiveness of IS for P (PO4-P) removal and emphasizes its pretreatment and longevity. A 4-d pretreatment of IS with 2.5 % NaCl resulted in a significant increase in P adsorption capacity, from approximately 1.0 to 2.5 mg/g. In column tests, the P removal efficiency remained above 60 % over 60 d, with a capacity of 4.1 mg P/g. Longevity tests involved seven adsorption-regeneration cycles, with an effective IS regeneration by 1 N NaOH and neutralization by HCl solution (pH=2), and the P adsorption capacity only slightly decreased from 2.14 to 1.75 mg P/g. To significantly improve the IS regeneration operation, we employed induction heating and compared an intermittent 10-s induction heating with an isothermal hot NaOH (85 ℃) treatment in 10-min desorption tests (95.3 % versus 56.6 % regeneration). We further found that IH completely regenerated IS in 5 min with 100 s of IH application, but 30 min were needed for hot NaOH (85 ℃) treatment. SEM/EDX, XRD, and XPS tests were conducted to track the changes in the morphology, crystallinity, and surface oxidation products of IS in the cycle tests. Notably, IS surface changed from coarse to smooth with fewer reactive sites and a higher conversion of amorphous Fe oxides to more crystalline Fe3O4, resulting in lower reactivity and fewer exposed Fe0 sites over multiple cycles. All of these mechanisms contributed to the deterioration in P removal capacity. Overall, this study provides a solid foundation for applying low-cost IS in effectively removing P from agricultural runoff.

Risk assessment of toxic and hazardous metals in paddy agroecosystem by biochar-for bio-membrane applications.

Toxic and carcinogenic metal (loid)s, such arsenic (As) and cadmium (Cd), found in contaminated paddy soils pose a serious danger to environmental sustainability. Their geochemical activities are complex, making it difficult to manage their contamination. Rice grown in Cd and As-polluted soils ends up in people's bellies, where it can cause cancer, anemia, and the deadly itai sickness. Solving this issue calls for research into eco-friendly and cost-effective remediation technology to lower rice's As and Cd levels. This research delves deeply into the origins of As and Cd in paddy soils, as well as their mobility, bioavailability, and uptake mechanisms by rice plants. It also examines the current methods and reactors used to lower As and Cd contamination in rice. Iron-modified biochar (Fe-BC) is a promising technology for reducing As and Cd toxicity in rice, improving soil health, and boosting rice's nutritional value. Biochar's physiochemical characteristics are enhanced by the addition of iron, making it a potent adsorbent for As and Cd ions. In conclusion, Fe-BC's biomembrane properties make them an attractive option for remediating As- and Cd-contaminated paddy soils. More efficient mitigation measures, including the use of biomembrane technology, can be developed when sustainable agriculture practices are combined with these technologies.

3D fractures analysis and conservation assessment of wrought iron javelin through advanced non-invasive techniques.

3D imaging is a powerful tool of high resolution and non-destructive imaging technology for the study of ancient weapons and military technology, which reveals the original microstructures and corrosion patterns that threaten these artefacts. Here we report quantitative analysis of the 3D distribution and the orientation of fractures, and uncorroded metal particles within a wrought iron javelin unearthed at the Phoenician-Punic site of Motya, Italy. The study aimed to gain a better understanding of the relationship between corrosion and local stresses within the artifact and to evaluate its manufacturing technology, as well as the effects of post-treatment with Paraloid B72 on concretion and mineralized layers. The cracks were quantified in terms of content, size, and orientation. The condition of artefact storage was evaluated by a multi-analytical approach, including X-ray microscopy, field emission electron microscopy and micro-Raman spectroscopy. The results indicated that a specific technique was used to create a sturdy, lightweight javelin with a central shaft for piercing or thrusting. The fractures appear elongated in the direction of the longitudinal axis of the blade, showing the forging direction of the original metallic block. The study concluded that the artifact had not yet been stabilized due to the presence of lepidocrocite.

Nano zero-valent iron enhances the absorption and transport of chromium in rice (Oryza sativa L.): Implication for Cr risks management in paddy fields.

Chromium (Cr) accumulating in soil caused serious pollution to cultivated land. At present, nano zero-valent iron (nZVI) is considered to be a promising remediation material for Cr-contaminated soil. However, the nZVI impact on the behavior of Cr in the soil-rice system under high natural geological background value remains unknown. We studied the effects of nZVI on the migration and transformation of Cr in paddy soil-rice by pot experiment. Three different doses of nZVI (0, 0.001 % and 0.1 % (w/w)) treatments and one dose of 0.1 % (w/w) nZVI treatment without plant rice were set up. Under continuous flooding conditions, nZVI significantly increased rice biomass compared with the control. At the same time, nZVI significantly promoted the reduction of Fe in the soil, increased the concentration of oxalate Fe and bioavailable Cr, then facilitated the absorption of Cr in rice roots and the transportation to the aboveground part. In addition, the enrichment of Fe(III)-reducing bacteria and sulfate-reducing bacteria in soil provided electron donors for Cr oxidation, which helps to form bioavailable Cr that is easily absorbed by plants. The results of this study can provide scientific basis and technical support for the remediation of Cr -polluted paddy soil with high geological background.

Technical and economical assessment of the treatment of vinasse from Pisco production using the advanced oxidation process.

The removal of organic matter from Pisco production wastewater was evaluated using coagulation/flocculation, filtration as a pre-treatment, and solar photo-Fenton, with the use of two types of photoreactors: compound parabolic collectors (CPC) and flat plate (FP), with and without utilizing the ozonation process. The overall removal efficiency for chemical oxygen demand (COD) was 63% and 15% using FP and CPC, respectively. Also, for the overall removal efficiency of polyphenols, a percentage of 73% and 43% were obtained using FP and CPC, respectively. When ozone was used in the solar photoreactors, the resulting trends were similar. COD and polyphenol removal, using an FP photoreactor in the solar photo-Fenton/O3 process, resulted in values of 98.8% and 86.2% after the process. COD and polyphenol removal, using solar photo-Fenton/O3 process in a CPC, resulted in values of 49.5% and 72.4%, respectively. The economic indicators of annual worth and economic treatment capacity established that FP reactors represent lower costs than CPCs. These results were corroborated by the economic analyses of the evolution of costs versus COD removed as well as by the cash flow diagrams projected for 5, 10, and 15 years.

Spatial distribution of elements, environmental effects, and economic potential of waste from the Aksu ferroalloy plant [Kazakhstan].

The utilization or secondary use of technogenic waste is a relevant problem for the current economy. To assess the environmental influence and economic potential, it is necessary to study the elemental content of technogenic objects and to reveal the tendencies of the spatial distribution of elements, components, and indices such as the pollution coefficient. In this study, we performed elemental analysis, and calculation of indicators: average gross content, hazard quotients, concentration coefficients of metals, and total pollution coefficients of ground samples taken from the ash-slag storage of the Aksu ferroalloy plant [Aksu, Pavlodar region, Kazakhstan]. Maps of the spatial distribution of concentrations of elements and total pollution coefficients were created. The territory of the studied ash-slag storage by the level of soil contamination should be considered as an environmental disaster zone. The given statistical data on the number of oncological and respiratory diseases indirectly indicated the negative influence of open storage of ash-slag waste. The studied ground was of chromium-manganese geochemical specialization. The calculated volume of the accumulated waste mass by the approximating method was 1 054 638.0 m3. The calculated approximate weight of the accumulated waste was 23 679 576.0864 tons, including 1 822 972.2 tons of chromium, 1 727 354.0 tons of manganese, and 953 813.3 tons of iron. The large amounts of valuable components retained in the waste mass led us to conclude that the studied technogenic object can be considered as a secondary field to produce various technological products. Moreover, valuable metals can be extracted as metal concentrates.

Biomonitoring and risk assessment of naturally and chemically synthesized iron-oxide nanoparticles: A comparative approach.

Nanostructured oxides and oxyhydroxides of iron are imperative constituents of the Earth's geological and biological processes i.e. biogeochemical cycles. So, the characteristic applications of iron oxide nanoparticles (FeONps) are closely linked to their surroundings and biological sinks. This work reports a low-cost green approach to promote 'waste-to-wealth' ideology by the direct and self-catalysis of iron rust into its nanoparticles (N-FeONps). A comparison is drawn based on the properties, morphologies, and applications after synthesizing FeONps by chemical precipitation method (C-FeONps). Spherical nanoparticles with vibrational properties are obtained in the size domain of 32 nm (N-FeONps) and 23 nm (C-FeONps). The application of Uniform deformation model, Uniform stress deformation model, Uniform deformation energy density model, and Size-strain plot models reveal comparatively greater defects in the crystal structures of C-FeONps. The biosafety profiling of natural and chemically designed nano-units performed on the species of bacteria, fungus, algae, and plants have shown enhanced safety terms associated with N-FeONps. The performance of N-FeONps has surpassed its chemical counterpart in medical applications such as antioxidant activity and anti-inflammatory activity with approximate percentages of 26 % and 51 % respectively. The findings of this piece of work favors the naturally obtained FeONps (N-FeONps), as they are economically viable, non-toxic, and have a greater antioxidant and anti-inflammatory arena. Hence, this waste-to-wealth ideology should be promoted for maintaining waste and designing solutions for the medical industries in one go.

A techno-economical assessment of treatment by coagulation-flocculation with aluminum and iron-bases coagulants of landfill leachate membrane concentrates.

Landfill leachate treatment involved with the membrane bioreactor (MBR) combined with membrane treatment via nanofiltration (NF) and/or reverse osmosis (RO) is widely used in Turkey. This treatment produces landfill leachate membrane concentrates (LLMCs) with an undesirably high concentration of contaminants. In the study, two different nanofiltration concentrates of leachate were coagulated. Coagulant dosages from 0.10 to 5.0 g of Me3+/L (Me3+: Al3+ or Fe3+), and the pH values ranged from 4.0 to 8.0 and 3.0-9.0 for Al-based and Fe-based coagulants, respectively. The most efficient pH values were 5.0 and 4.0 for Al3+ and Fe3+, respectively. These pH values are lower than those known to be effective in coagulants. The reason for this is the presence of humic substances in the wastewater. The cost of Fe2(SO4)3.xH2O was the lowest than other coagulants at the end of the cost analyses obtained from Istanbul region landfill leachate NF concentrate (NFCL-1) and Kocaeli region landfill leachate NF concentrate (NFCL-2). Under optimum conditions, the costs for NFCL-1 and NFCL-2 were calculated as 0.55 and 0.46 $/removed kg COD, respectively.