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This study emphasis on the feasibility of a vegetable biosorbent Tamarix aphylla (TA) for both cationic and anionic dyes adsorption. Indeed, this plant improves its efficiency for cationic Safranin and anionic Remazol Brilliant Blue R (RBBR) dyes removal from aqueous solutions. Firstly, the physico-chemical proprieties of the stem of T. aphylla (TA) were determined by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The functional groups of T. aphylla before and after adsorption process were also determined. The parameters optimization (solution pH, biosorbent amount, biosorbent size fraction, initial dye concentration, reaction time) were taken place to control the best conditions for the adsorption process. The results showed that acidic pH (2.0) was more suitable for RBBR adsorption; however, a basic medium (pH: 8.0) was more suitable for Safranin adsorption. The pseudo-second-order model appears the suitable models for both dyes adsorption. Moreover, Temkin was the best fitting isotherm for both dyes with the highest correlation value of R2 (0.9988) and (0.9795) for Safranin and RBBR, respectively. These results explain that chemisorption of dyes takes place on the heterogeneous biomass surface. In addition, this adsorption occurred spontaneously due to the endothermic nature of the reaction. This scientific study offers a solution for colored wastewater treatment using the raw vegetable biomass T. aphylla (TA) without further chemical treatment. [ABSTRACT FROM AUTHOR]

The current study proposed a novel simple and environmentally friendly approach for producing silver nanoparticles (AgNPs) using an extract of Moringa oleifera leaves (MOL) and optimizing the different experimental factors required for the formation and stability of AgNPs. The formation of nanoparticles was confirmed by a color change from yellow to reddish-brown with a surface plasmon resonance band at 412 nm. The morphology, size, and elemental composition of AgNPs were investigated by zeta potential dynamic light scattering, field emission scanning electron microscopy, energy dispersive X-ray, X-ray diffraction, and transmission electron microscopy analysis, which showed crystalline and spherical AgNPs. The identification of functional groups was supported by Fourier-transform infrared spectroscopy. The photocatalytic activities of AgNPs were assessed in the degradation of organic Malachite green (MG) dye in the aqueous solution. Two kinetic adsorption models, the pseudo-first-order model and the pseudo-second-order model, and three isotherm models, the Langmuir, Freundlich, and Temkin, were used to mathematically characterize the MG degradation process. The pseudo-second-order kinetics and the Freundlich isotherm model were found to be in good agreement with the experimental data. As a result of their synergistic interaction with the MOL extract solution, the photocatalytic activity of AgNPs increases and they can successfully adapt to the photodegradation of organic dyes in industrial effluents.

The study investigated the utilization of waste palm fiber as an adsorbent for methylene blue (MB) removal. The waste palm fiber was treated by a series of steps to prepare an activated charcoal adsorbent. The adsorption process of MB on the activated charcoal was modeled using the Box-Behnken design (BBD) in the response surface methodology (RSM). Adsorbent mass, solution pH, temperature, and time were selected as factors, while removal efficiency and adsorption capacity were chosen as responses. Both models were significant with correlation factors of 0.85 and 0.99 for removal efficiency and adsorption capacity, respectively. Optimal conditions for MB removal were achieved at an initial pH of 7, an adsorbent dose of 0.05 g/L, and a contact time of 30 min, resulting in a 99% removal efficiency. The adsorption of MB using the activated charcoal indicates the physical nature of the reaction., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The study examines the immobilization of the urease enzyme on a range of High Internal Phase Emulsion (polyHIPE) materials, assessing characteristics, efficiency, and performance. It also investigates the impact of polyHIPE type, quantity, incubation time, and various parameters on the process and enzyme activity. Surface morphology and functional groups of polyHIPE materials were determined through scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR) analyses, revealing significant alterations after modification with polyglutaraldehyde (PGA). The maximum immobilization efficiency of 95% was achieved by adding PGA to polyHIPE materials with an incubation period of 15 h. The optimized conditions for immobilized enzyme using a Box-Behnken design (BBD) of response surface methodology (RSM) were as follows: temperature (40.8 °C), pH (7.1) and NaCl concentration (0.007 g/L). Furthermore, the immobilized enzyme demonstrated remarkable reusability, retaining 75% of its initial activity after six cycles, and sustained shelf-life stability, retaining over 40% activity after 10 days at room temperature. Kinetic analyses revealed that immobilized urease exhibited higher affinity for the substrate, but lower rate of substrate conversion compared to the free enzyme. These findings offer valuable insights into optimizing urease immobilization processes and enhancing urease stability and activity, with potential applications in various fields, including biotechnology and biocatalysis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study explores the incorporation of Nb 2 AlC and Mo 3 AlC 2 MAX phases, known for their nano-layered structure, into polyether sulfone (PES) membranes to enhance their antifouling and permeability properties for pathogen microorganism filtration against bovine serum albumin (BSA) and Escherichia coli (E. coli). The composite membranes were characterized for their structural and morphological properties, and their performance in mitigating biofouling was evaluated. The structural characterizations have been performed for all the prepared MAX phases and corresponding composite membranes. The antioxidant ability of Nb 2 AlC and Mo 3 AlC 2 MAX phases was defined by the DPPH radical scavenging assay, and the highest antioxidant ability was found to be 59.35 %, while 53.69 % scavenging potential was recorded at 100 mg/L. The percentage scavenging ability was raised with an increase in concentrations. The antimicrobial properties of MAX phases, evaluated as the minimum inhibitory concentration, were stated against several pathogen microorganisms. The tested compounds of Nb 2 AlC and Mo 3 AlC 2 composites containing MAX phases exhibited excellent chemical nuclease activity, and it was determined that Nb 2 AlC caused double strand DNA cleavage activity while Mo 3 AlC 2 induced the complete fragmentation of the DNA molecule. Biofilm inhibition of Nb 2 AlC and Mo 3 AlC 2 MAX phases was studied against Staphylococcus aureus, and Pseudomonas aeruginosa and the maximum biofilm inhibition of Nb 2 AlC and Mo 3 AlC 2 MAX phases was found to be 77.15 % and 69.07 % against S. aureus and also 69.74 % and 65.01 % against P. aeruginosa. Furthermore, Nb 2 AlC and Mo 3 AlC 2 MAX phases demonstrated excellent E. coli growth inhibition of 100 % at 125 and 250 mg/L., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biohydrogen is considered an alternative energy reserve. Dark fermentation is one of the important green hydrogen production techniques that utilizes organic waste as raw material. It is a promising bioconversion, easy, not expensive, and cost-effective process. Milk processing wastewater (MPWW) is an organic effluent generated in large volumes on a daily basis and disposed directly into the environment. In this research, the study of biochemical hydrogen potential (BHP) test of MPWW was evaluated and used as substrate (S). A waste sludge was used as an inoculum (I) and source of bacteria. Both substrate and inoculum were analyzed and the study was based mainly on the ratio of volatile solids (VS) of inoculum and substrate subsequently, which was noted as I/S. Different substrate pretreatments were performed: ultrasonic, thermal, chemical, and enzymatic hydrolysis. The I/S ratio impact was investigated and evaluated the hydrogen production improvement. Modified Gompertz and modified Logistic kinetic models were employed for the kinetic modeling of cumulative hydrogen production values. Results show that I/S ratio of 1/4 gVS/gVS resulted from the best hydrogen production of 59.96 mL during 30 days of MPWW fermentation without pretreatment. It was also shown that all the adopted pretreatments enhanced hydrogen production, whereas ultrasonic pretreatment for 5 min increased the production by only 14.84%. Heat pretreatment was more efficient, where the hydrogen production increased from 60 to 162 mL (170% of improvement) using heat shock at 90 °C for 30 min. The impact of chemical pretreatment was different from a reagent to another. Pretreatment using calcium hydroxide resulted in the biggest hydrogen production of 165.3 mL (175.5%) compared to the other chemical pretreatments. However, the best hydrogen production was given by the biological pretreatment using enzymatic hydrolysis (Lactase) resulting in 254 mL of hydrogen production, which is equivalent to 323.62% of production improvement. Modified Gompertz and Logistic kinetic models fitted well with experimental data. Thus, the enzymatic hydrolysis of MPWW proved to be a promising technique for biohydrogen production enhancement., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This study investigated the treatment of wastewater from tomato paste (TP) production using electrocoagulation (EC) and electrooxidation (EO). The effectiveness of water recovery from the pretreated water was then investigated using the membrane process. For this purpose, the effects of independent control variables, including electrode type (aluminum, iron, graphite, and stainless steel), current density (25-75 A/m 2 ), and electrolysis time (15-120 min) on chemical oxygen demand (COD) and color removal were investigated. The results showed that 81.0% of COD and 100% of the color removal were achieved by EC at a current density of 75 A/m 2 , a pH of 6.84 and a reaction time of 120 min aluminum electrodes. In comparison, EO with graphite electrodes achieved 55.6% of COD and 100% of the color removal under similar conditions. The operating cost was calculated to be in the range of $0.56-30.62/m 3 . Overall, the results indicate that EO with graphite electrodes is a promising pretreatment process for the removal of various organics. In the membrane process, NP030, NP010, and NF90 membranes were used at a volume of 250 mL and 5 bar. A significant COD removal rate of 94% was achieved with the membrane. The combination of EC and the membrane process demonstrated the feasibility of water recovery from TP wastewater., Competing Interests: The authors declare there is no conflict., (© 2024 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).)

Biological pretreatment and enzymatic hydrolysis have a potential role in the economic production of sugars and fuels from starch biomass. In this study, the Inoculum/Substrate (I/S) ratio effect and enzymatic pretreatments of potato peels for biohydrogen production in batch reactors were investigated. Two enzymes, α- Amylase and Cellulase , were tested separately and coexistent. Results showed that enzymatic hydrolysis using α- Amylase in mesophilic conditions enhanced carbohydrate concentration from 24.10 g/L to 53.47 g/L, whereas, the use of Cellulase and equi-volumetric mixture of both tested enzymes resulted in 47.16 and 48.16 g/L, respectively. The maximum biohydrogen cumulative production of 263 mL (equivalent to 430.37 mL H 2 /gVS added ) was obtained using the optimum I/S ratio of 1/6 gVS/gVS at pH 5.5 and incubation temperature of 55°C after 20 days of dark fermentation of potato waste without enzymatic treatment. Under the same operating conditions of the I/S ratio, pH, temperature and the best enzymatic treatment (3 h of substrate enzymatic hydrolysis by α- Amylase), the maximum yield of biohydrogen was 1088 mL (1780.39 mL H 2 /gVS added ). The enzymatic hydrolysis method adopted in this study can make overall biohydrogen production an effective process. The modified Gompertz model was found to be an adequate fit for biohydrogen production.

Chromium aluminum carbide (Cr 2 AlC) MAX phase and Cr 2 CT x (MXene-Cr) were synthesized by the pressureless sintering method and hydrothermal method, respectively. In addition to this, the free radical scavenging activities (FRSA) of MAX-Cr phase and MXene-Cr compounds were tested and compared with ascorbic acid and trolox as standard compounds. The obtained FRSA results of MAX-Cr phase and MXene-Cr were 42.82 and 59.64%, respectively, at 100 mg/L concentration. MXene-Cr showed a 66.90% inhibitory effect on α-amylase at 200 mg/L. The DNA nuclease activity of compounds was determined to be extremely satisfactory at 50, 100, and 200 mg/L concentrations. Moreover, the prepared MAX-Cr phase and MXene-Cr were investigated for antimicrobial activity against six bacterial and two fungal strains by the broth microdilution method. Compounds provided more significant inhibition against Gram-positive bacteria than Gram-negative bacteria and fungi. MAX-Cr phase and MXene-Cr almost completely inhibited microbial cell viability at a 25 mg/L concentration. Additionally, MXene-Cr showed 89.86% and 87.01% antibiofilm activity against S. aureus and P. aeruginosa, respectively, while the antibiofilm activity of the MAX-Cr phase was over 90%., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This paper illustrates the gas adsorption properties of newly synthesized nanoporous cross-linked polymer networks (CPNs). All synthesized CPNs possess N-rich functional groups and are used for the utilization of carbon dioxide and methane. Good gas adsorption and selectivities are obtained for all of the samples. Among the materials, HEREON2 outperforms better selectivity for methane separation from nitrogen rather than zeolites, activated carbons, molecular sieves, covalent organic frameworks, and metal-organic frameworks (MOFs). The accessibility of the N-rich functionalities makes these materials potential candidates for the separation of hydrocarbons via increased polarizabilities. High-pressure adsorption experiments showed that the synthesized two-dimensional nanoporous materials also have a high affinity toward carbon dioxide. HEREON2 powders showed an increased experimental CO 2 /N 2 selectivity of ∼25,000 at 50 bar due to the presence of nitrogen groups in the structure. Fourier-transform infrared spectroscopy (FTIR), solid-state NMR, X-ray diffraction, thermogravimetric analysis, energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were applied for the characterization of the synthesized nanoporous CPNs. The results show a potential new pathway for future CPN membrane development., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Search for new antimicrobial agents is of great significance due to the issue of antimicrobial resistance, which nowadays has become more important than many diseases. The aim of this study was to evaluate the toxicity and biological effects of a dextran-graft-polyacrylamide (D-PAA) polymer-nanocarrier with/without silver or gold nanoparticles (AgNPs/D-PAA and AuNPs/D-PAA, respectively) to analyze their potential to replace or supplement conventional antibiotic therapy. The toxicity of nanocomplexes against eukaryotic cells was assessed on primary dermal fibroblasts using scratch, micronucleus and proliferation assays. DPPH (2,2-diphenyl-1-picrylhydrazylradical) assay was used to evaluate the antioxidant capacity of D-PAA, AgNPs/D-PAA and AuNPs/D-PAA. DNA cleavage, antimicrobial and biofilm inhibition effects of nanocomplexes were investigated. Nanocomplexes were found to be of moderate toxicity against fibroblasts with no genotoxicity observed. AgNPs/D-PAA reduced motility and proliferation at lower concentrations compared with the other studied nanomaterials. AgNPs/D-PAA and AuNPs/D-PAA showed radical scavenging capacities in a dose-dependent manner. The antimicrobial activity of AgNPs/D-PAA against various bacteria was found to be much higher compared to D-PAA and AuNPs/D-PAA, especially against E. hirae, E. faecalis and S. aureus, respectively. D-PAA, AgNPs/D-PAA and AuNPs/D-PAA showed DNA-cleaving and biofilm inhibitory activity, while AgNPs/D-PAA displayed the highest anti-biofilm activity. AgNPs/D-PAA and AuNPs/D-PAA were characterized by good antimicrobial activity. According to the findings of the study, AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of new antimicrobial agents, the fight against biofilms, sterilization and disinfection processes. Our findings confirm the versatility of nanosystems based on dextran-polyacrylamide polymers and indicate that AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of novel antimicrobial agents., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

In this investigation, two new thermophilic bacteria were isolated. The new isolates were characterized by 16S rRNA, biochemical, morphological, and physiological analyzes and the isolates were identified as Geobacillus stearothermophilus strain Gecek20 and thermophilic Anoxybacillus flavithermus strain Gecek19. Various biological activities of extracellular Ag-NPs synthesized from thermophilic G. stearothermophilus strain Gecek20 and thermophilic A. flavithermus strain Gecek19 were evaluated. The produced NPs were analyzed by SEM, SEM-EDX, and XRD analyses. The antioxidant abilities of new synthesized Ag-NPs from thermophilic G. stearothermophilus strain Gecek20 (T1-Ag-NPs) and new synthesized Ag-NPs from thermophilic A. flavithermus strain Gecek19 (T2-Ag-NPs) were studied by DPPH inhibition and metal chelating ability. The highest DPPH and metal chelating abilities of T1-Ag-NPs and T2-Ag-NPs at 200 mg/L concentration were 93.17 and 90.85%, and 75.80 and 83.64%, respectively. The extracellular green synthesized T1-Ag-NPs and T2-AgN-Ps showed DNA nuclease activity at all tested concentrations. Moreover, both new synthesized Ag-NPs had antimicrobial activity against the strains studied, especially on Gram positive bacteria. T1-Ag-NPs and T2-AgNPs also showed powerful Escherichia coli growth inhibition. The highest biofilm inhibition percentages of T1-Ag-NPs and T2-Ag-NPs against Pseudomonas aeruginosa and Staphylococcus aureus were 100.0%, respectively, at 500 mg/L.

Serious global problems faced due to many petroleum-based materials in the last century, which is called the plastic age, constitute the main motivation of this research. Considering wastewater treatment from this perspective, both the recovery of organic acids from wastewater and their conversion into bioplastics are extremely important in terms of reducing petroleum dependency. In this study, while the treatment of landfill leachate was provided with biological process integrated into Mechanical Vapor Recompression (MVR), simultaneously PHBV production was carried out with 84.9% recovered VFA as carbon source. The effects of C/N/P ratio and feeding regime on PHBV storage were investigated by Cupriavidus necator. PHBV storage of 96% (g PHBV/g DCW) was maximized by 2-stage feeding and nitrogen restriction. The ratio of 3HV to 3HB of PHBV was 45%. In addition, extracted PHBV was compared with standard PHA in terms of thermal and chemical properties with FTIR, XRD, TGA and DSC analyses., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ahmet Karagunduz reports financial support was provided by Scientific and Technological Research Council of Turkey (TUBITAK)., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Antimicrobial resistance to antibiotics for current bacterial infection treatments is a medical problem. 2D nanoparticles, which can be used as both antibiotic carriers and direct antibacterial agents due to their large surface areas and direct contact with the cell membrane, are important alternatives in solving this problem. This study focuses on the effects of a new generation borophene derivative obtained from MgB 2 particles on the antimicrobial activity of polyethersulfone membranes. MgB 2 nanosheets were created by mechanically separating magnesium diboride (MgB 2 ) particles into layers. The samples were microstructurally characterized using SEM, HR-TEM, and XRD methods. MgB 2 nanosheets were screened for various biological activities such as antioxidant, DNA nuclease, antimicrobial, microbial cell viability inhibition, and antibiofilm activities. The antioxidant activity of nanosheets was 75.24 ± 4.15% at 200 mg/L. Plasmid DNA was entirely degraded at 125 and 250 mg/L nanosheet concentrations. MgB 2 nanosheets exhibited a potential antimicrobial effect against tested strains. The cell viability inhibitory effect of the MgB 2 nanosheets was 99.7 ± 5.78%, 99.89 ± 6.02%, and 100 ± 5.84% at 12.5 mg/L, 25 mg/L, and 50 mg/L, respectively. The antibiofilm activity of MgB 2 nanosheets against S. aureus and P. aeruginosa was observed to be satisfactory. Furthermore, a polyethersulfone (PES) membrane was prepared by blending MgB 2 nanosheets from 0.5 wt to 2.0 wt %. Pristine PES membrane also has shown the lowest steady-state fluxes at 30.1 ± 2.1 and 56.6 L/m 2 h for BSA and E. coli, respectively. With the increase of MgB 2 nanosheets amount from 0.5 to 2.0 wt%, steady-state fluxes increased from 32.3 ± 2.5 to 42.0 ± 1.0 and from 15.6 ± 0.7 to 24.1 ± 0.8 L/m 2 h, respectively for BSA and E. coli. E. coli elimination performance of PES membrane coated with MgB 2 nanosheets at different rates and the membrane filtration procedure was obtained from 96% to 100%. The results depicted that BSA and E. coli rejection efficiencies of MgB 2 nanosheets blended PES membranes increased when compared to pristine PES membranes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Today, where water resources are polluted rapidly, the need for eco-friendly green methods is gradually increasing. Conversion of waste biomass into functional adsorbents that can be utilized in water treatment is a win-win practice for both recycling and water pollution treatment. In this study, the adsorbent material was obtained from the palm leaf to contribute to sustainable green energy. This cellulose-containing adsorbent material was tested in the removal of Methylene Blue (MB) and Basic Red-18 (BR18). The properties of palm leaf adsorbent were determined. The best removal efficiencies and optimum conditions were determined in the adsorption process. In both dye types; the original pH value, 2 g/L adsorbent dose, 25 mg/L dye concentration, and 120 min were chosen as the optimum conditions since the best removal efficiency was obtained in the experiments performed at 25 °C. At these conditions, the removal efficiencies were found to be 100% and 90% for BR18 and MB, respectively. In addition, adsorption kinetics, isotherms, and thermodynamic data were analyzed. For BR18 and MB, it was found to fit the Langmuir isotherm and pseudo-2nd order. Palm leaf adsorbent was used with an efficiency of over 50% in four consecutive cycles., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

There are several studies stating that many types of microplastics cannot be retained completely by conventional wastewater treatment systems. Therefore, it is necessary to prevent the discharge of these microplastics to the ecological system. The objective of this study was to investigate the biodegradation ability of two different size of PE (50 and 150 µm) by using two Gram-positive, spore-forming, rod-shaped, and motile thermophilic bacteria, called strain Gecek4 and strain ST5, which can hydrolyse starch, were isolated from the soil's samples of Gecek and Ömer hot-springs in Afyonkarahisar, Turkey, respectively. Phenotypic features and 16S rRNA analyzing of strains also studied. According to these results, Gecek4s and ST5 were identified as Anoxybacillus flavithermus Gecek4s and Bacillus firmus ST5, respectively. Results showed that A. flavithermus Gecek4s could colonise the polymer surface and cause surface damage whereas B. firmus ST5 could not degrade bigger-sized particles efficiently. In addition, morphological changes on microplastic surface were investigated by scanning electron microscopy (SEM) where dimensional changes, irregularities, crack, and/or holes were detected. This finding suggests that there is a high potential to develop an effective integrated method for plastic bags degradation by extracellular enzymes from bacteria.

In this study, color removal, suspended solids removal, and salt recovery were investigated from different fabric dyeing wastewaters using a pilot scale treatment system. A pilot scale system was installed in the wastewater outlet area of five different textile companies. Experiments were planned for pollutant removal and salt recovery from wastewater. First, the wastewater was treated by electrooxidation (EO) using graphite electrodes. After a reaction time of 1 h, the wastewater was passed throughout the granular activated carbon (AC) coloumn. The pre-treated wastewater was passed through the membrane (NF) system to recover the salt in the wastewater. Finally, the recovered salt water was used for fabric dyeing. In the pilot scale treatment system (EO + AC + NF), 100% of suspended solids (SS) and an average of 99.37% of color were removed from fabric dyeing wastewaters. At the same time, a high amount of salt water was recovered and reused. Optimum conditions were determined as 4 V current, 1000 A power, wastewater's own pH values and 60 min of reaction time. The energy and operating cost for treatment of 1 m 3 of wastewater were determined as 40.0 kWh/m 3 and 2.2 US$/m 3 , respectively. In addition to the prevention of environmental pollution by the treatment of wastewater using the pilot-scale treatment system, the reuse of the recovered water will contribute to the protection of our valuable water resources. In addition, using the NF membrane process after the EO system, it will be possible to recover salt from wastewater with high salt content such as textile wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The wastewater generated from citric acid production has a high organic loading content. The treatment and reuse of citric acid wastewater with high organic loading become extremely important. In this study, the performance of calcium hydroxide (Ca(OH) 2 ) precipitation as a low-cost and environmentally friendly pre-treatment method and aerobic membrane bioreactor (MBR) combined treatment system was investigated for the treatment of citric acid (CA) wastewater. At the first step, optimization parameters such as agitation speed (100, 150, 200 rpm), temperature (30, 50, 70 °C), and reaction time (2, 4, 6 h) for Ca(OH) 2 precipitation as a pre-treatment method were investigated using response surface methodology (RSM) to achieve maximum chemical oxygen demand (COD) removal. Experimental sets were designed using Box-Behnken Design. As a result of pre-treatment with Ca(OH) 2 precipitation, a COD removal efficiency of 97.3% was obtained. Then, pre-treated CA wastewater was fed continuously to the MBR process for 10 days, which was the second stage of the combined process. As a result of the MBR process, 92.0% COD removal efficiency was obtained for 24 h HRT and 10 days SRT. In total, 99.8% COD removal efficiency was obtained when combined process was used and COD concentration decreased from 52,000-114 mg/L. For the treatment and reuse of wastewater from citric acid production, Ca(OH) 2 precipitation and MBR combined treatment systems demonstrated an effective strategy., Competing Interests: Declaration of competing interest The authors whose names are listed immediately below certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Membrane fouling is a serious handicap of membrane-based separation, as it reduces permeation flux and hence increases operational and maintenance expenses. Polyurethane-paraffin wax (PU/PW) nanocapsules were integrated into the polyethersulfone membrane to manufacture a composite membrane with higher antifouling and permeability performance against humic acid (HA) and bovine serum albumin (BSA) foulants. All manufactured membranes were characterized by scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), and contact angle. The contact angle of the pristine polyethersulfone (PES) membrane was measured 73.40 ± 1.32. With the embedding of nanocapsules, the contact angle decreased to 64.55 ± 1.23 for PES/PU/PW 2.0 wt%, and the pure water flux of all composite membranes increased when compared to pristine PES. The pristine PES membrane also has shown the lowest steady-state fluxes at 45.84 and 46.59 L/m 2 h for BSA and HA, respectively. With the increase of PU/PW nanocapsule ratio from 0.5 to 1.0 wt%, steady-state fluxes increased from 51.96 to 71.61 and from 67.87 to 98.73 L/m 2 h, respectively, for BSA and HA. The results depicted that BSA and HA rejection efficiencies of PU/PW nanocapsules blended PES membranes increased when compared to pristine PES membranes.

Phosphorus (P) problem worries the whole world due to the increasing demand for finite and non-renewable natural phosphate resources and the inadequacy of sustainable phosphate production technologies. In this study, bio-acidification processes using waste sludge and food waste for simultaneous sustainable phosphate release and biogas production were investigated. Response surface methodology (RSM) was used for bio-acidification optimization. High performance was achieved with the addition of 10% FW and a temperature of 45 °C, which provided 5.30 pH and 371 mg/L P release for 10 days. A total of 196 mL of cumulative biogas was produced. Using food waste potentially reduces operating costs, eliminating the need for external chemical additions for pH control. Also, this approach offers benefits such as waste management, recovery of valuable resources, cost reduction, and environmental friendly., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

It is known that heavy metal containing nanomaterials can easily prevent the formation of microbial cultures. The emergence of new generation epidemic diseases in the last 2 years has increased the importance of both personal and environmental hygiene. For this reason, in addition to preventing the spread of diseases, studies on alternative disinfectant substances are also carried out. In this study, the antibacterial activity of nanoflower and nanocube, which are easily synthesized and nanoparticle species containing iron, were compared. The antioxidant abilities of new synthesized NF@FeO(OH) and NC@α-Fe 2 O 3 were tested by DPPH scavenging activity assay. The highest DPPH inhibition was achieved with NC@α-Fe 2 O 3 as 71.30% at 200 mg/L. NF@FeO(OH) and NC@α-Fe 2 O 3 demonstrated excellent DNA cleavage ability. The antimicrobial capabilities of NF@FeO(OH) and NC@α-Fe 2 O 3 were analyzed with micro dilution procedure. In 500 mg/L, the antimicrobial activity was 100%. In addition to these, the biofilm inhibition of NF@FeO(OH) and NC@α-Fe 2 O 3 were investigated against S. aureus and P. aeruginosa and it was found that they showed significant antibiofilm inhibition. It is suggested that additional studies can be continued to be developed and used as an antibacterial according to the results of the nanoparticles after various toxicological test systems., Supplementary Information: The online version contains supplementary material available at 10.1007/s13204-023-02822-5., Competing Interests: Conflict of interestThe author declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© King Abdulaziz City for Science and Technology 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Disinfection can be accomplished by adding external chemical agents to kill harmful microorganisms or by removing them using membranes. However, most chemicals are toxic for humans and animals if it is consumed above a certain concentration. Likewise, membranes have fouling problems. The aim of this study is to investigate the effect of diode laser, which is an environmentally friendly application, on pathogenic microorganisms such as Escherichia coli (ATCC 10536), Staphylococcus aureus (ATCC 6538) and Candida albicans. To reveal the effect of diode laser on aforementioned, various parameters have been studied on how diode laser type, laser irradiation time, laser power density, laser penetration efficiency and biofilm inhibition affect microorganisms. As a result of the study, it was observed that the blue laser was more effective than red and green lasers, and the inhibition rates for 15 min at 0.36 W/cm 2 laser power density were 65.9% > 34.52% > 43.63% for S. aureus , E. coli and C. albicans , respectively. After 30 min of blue laser irradiation, the microbial growth inhibitions were found as 85.39%, 41.18% and 54.55% for S. aureus , E. coli and C. albicans , respectively. The highest biofilm inhibition was 94.61% when S. aureus cells were exposed to blue laser irradiation for 60 min. The microbial growth kinetics on three microorganisms were tested by using at 0.54 W/cm 2 laser power density for 28 h, and there were not observed any microbial development in microbial cultures. Moreover, blue laser irradiation was successfully disinfected wastewater and natural milk at 0.54 W/cm 2 laser power density.

The control over bacterial diseases requires the development of novel antibacterial agents. The use of antibacterial nanomedicines is one of the strategies to tackle antibiotic resistance. The study was designed to assess the antimicrobial activity of cerium oxide (CeO 2 ) nanoparticles (NP) of two different sizes (CeO 2 NP1 [1-2 nm] and CeO 2 NP2 [10-12 nm]) and their cytotoxicity towards eukaryotic cells. The antimicrobial activity, effects of nanoparticles on DNA cleavage, microbial cell viability, and biofilm formation inhibition were analyzed. The impact of cerium oxide nanoparticles on eryptosis of erythrocytes was estimated using annexin V staining by flow cytometry. The newly synthesized CeO 2 NP1 and CeO 2 NP2 displayed moderate antimicrobial activities. CeO 2 NP1 and CeO 2 NP2 exhibited single-strand DNA cleavage ability. CeO 2 NPs were found to show 100% microbial cell viability inhibition at a concentration of 500 mg/L. In addition, CeO 2 NP1 and CeO 2 NP2 inhibited the biofilm formation of S. aureus and P. aeruginosa. Larger cerium oxide nanoparticles were found to be less toxic against erythrocytes compared with the smaller ones. CeO 2 nanoparticles demonstrate moderate antimicrobial activity and low cytotoxicity towards erythrocytes, which make them promising antibacterial agents., (© 2022 Wiley Periodicals LLC.)

Antibacterial membranes have attracted researchers' interest in recent years as a possible approach for dealing with biofouling on the membrane surface. This research aims to see if blending AZ63 Mg alloy into a polyethersulphone (PES) membrane can improve antifouling and separation properties. The composite membranes' pure water flux continued to increase from pristine PES to PES/AZ63 2.00 wt%. The results showed that PES/AZ63 2.00 wt% membrane supplied the highest permeate flux of E. coli. The steady-state fluxes of AZ63 composite membranes were 113.24, 104.38 and 44.79 L/m 2 h for PES/AZ63 2.00 wt%, 1.00 wt%, and 0.50 wt%, respectively. The enhanced biological activity of AZ63 was studied based on antioxidant activity, DNA cleavage, antimicrobial, anti-biofilm, bacterial viability inhibition and photodynamic antimicrobial therapy studies. The maximum DPPH scavenging activity was determined as 81.25% with AZ63. AZ63 indicated good chemical nuclease activity and also showed moderate antimicrobial activity against studied strains. The highest biofilm inhibition of AZ63 was 83.25% and 71.63% towards P. aeruginosa and S. aureus, respectively. The cell viability inhibition activity of AZ63 was found as 96.34% against E. coli. The photodynamic antimicrobial therapy results displayed that AZ63 demonstrated 100% bacterial inhibition when using E. coli.

An alternative biotechnological solid phase bio-extraction (SPE) method was developed. Bacillus subtilis loaded multiwalled carbon nanotube was designed and used as biosorbent for the preconcentrations of Pb(II), Ni(II), and Zn(II). The experimental parameters such as sample flow rate, pH of sample solution, amounts of Bacillus subtilis and multiwalled carbon nanotube, volume of sample solution and reusability of column which affects the analytical characteristics of the SPE method were investigated in details. Surface structures were examined by using FTIR, SEM. The best pH was determined as 5.0 and the percentages recoveries of Zn(II), Ni(II), and Pb(II) were determined as 99.1%, 98.7%, and 96.2%, respectively, at a flow rate of 3 mL/min. In this study, in which the profitable sample volume was determined as 400 mL and the amount of multiwalled carbon nanotube (MWCNT) as 50 mg. It was also observed that the column had a significant potential to preconcentrate Zn(II), Ni(II), and Pb(II) even after 25 reuses. The biosorption capacities for Zn(II), Ni(II) and Pb(II) were calculated as 39.67 mg/g, 45.98 mg/g and 51.34 mg/g respectively. The LOD values were calculated as 0.024 ng/mL for Pb(II), 0.029 ng/mL for Ni(II), and 0.019 ng/mL for Zn(II). The linear range was detected as 0.25-25 ng/mL. The concentrations of Pb(II), Ni(II), and Zn(II) in a variety of real food samples were determined by using developed method after application of certified reference sample., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this research, nanoparticles derived from water extract of Centaurea solstitialis leaves were used as green adsorbent in Fenton reaction for Reactive Red 180 (RR180) and Basic Red 18 (BR18) dyes removal. At optimum operating conditions, nanoparticles proved high performance in the tested dyes removal with more than 98% of removal elimination. The free-radical scavenging, DNA nuclease, biofilm inhibition capability, antimicrobial activity, microbial cell viability, and antimicrobial photodynamic therapy activities of the iron oxide nanoparticles (FeO-NPs) derived from water and methanol extract of plant were investigated. Each of the following analysis: SEM-EDX, XRD, and Zeta potential was implemented for the prepared NPs characterization and to describe their morphology, composition and its behavior in an aqueous solution, respectively. It was found that, the DPPH scavenging activities increased when the amount of nanoparticles increased. The highest radical scavenging activity achieved with FeO-NPs derived from water extract of plant as 97.41% at 200 mg/L. The new green synthesized FeO-NPs demonstrated good DNA cleavage activity. FeO-NPs showed good in vitro antimicrobial activities against human pathogens. The results showed that both synthesized FeO-NPs displayed 100% antimicrobial photodynamic therapy activity after LED irradiation. The water extract of FeO-NPs and methanol extract of FeO-NPs also showed a significant biofilm inhibition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The use of synthetic dyes in the textile industry pollutes a huge amount of water. Thus, wastewater discharged from many textile companies to the receiving environment without being treated causes serious environmental and human health problems. The development of new techniques has become imperative. In this study, it was aimed to remove anionic dye (RR180) and cationic dye (BR18) by Fenton-like and adsorption process with hydrochars obtained from laurel leaves and watermelon peels. In the comparison of the adsorption and Fenton-like processes used in the dye removal of the produced bio-based materials, the Fenton-like process was selected in order to enhance the highest removal efficiency. The effects of various operating factors such as solution pH, amount of catalysts, hydrogen peroxide (H 2 O 2 ) concentration, and initial dye concentration were evaluated on both dyes removal. The experimental results demonstrated that 99.8% RR180 dye and 98.8% BR18 dye removal efficiency were observed for an initial dye concentration of 100 mg/L with an adsorbent concentration of 1 g/L, H 2 O 2 concentration of 15 μL/L, and optimum pH at the end of 60 min of reaction time. It was observed that an increase in initial dye concentration caused to decrease the dye removal efficiency. The optimum pH for the highest RR180 and BR18 dye removal was 4 and 6, respectively. It was observed that the increase in H 2 O 2 concentration in the solution also decreased the dye removal efficiency. It turned out that catalysts obtained from hydrochars are an effective process for the high removal performance of cationic and anionic dyes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this study, antioxidant (DPPH and metal chelating), DNA cleavage, biofilm, and antimicrobial properties of extracted phenol from the walnut green husk (WGH) and its different concentrate and permeate samples were evaluated. For maximum phenolic compound extraction from the WGH first, the effects of solvent type (deionized water, methanol, n-hexane, acetone, and ethanol), solvent temperature (25-75 °C), and extraction time (0.5-24 h) were optimized. Then to concentrate phenolic compounds a pressure-driven membrane process was used with four different membrane types. The phenol contents of the concentrate samples were found to be microfiltration (MF) concentrate 4400 mg/L, ultrafiltration (UF) concentrate 4175 mg/L, nanofiltration (NF) concentrate 8155 mg/L, and reverse osmosis (RO) concentrate 8100 mg/L. LC-MSMS was used to determine the quantification of phenolic compounds in permeate and concentrate streams. In addition, all of the concentrate samples with high phenol content showed a high antioxidant activity as 100% with MF concentrate, UF concentrate, NF concentrated and RO concentrated. Likewise, concentrate samples were found to have very high antibiofilm activity as 82.86% for NF concentrate againts S. aureus , 85.80% for NF concentrate against P. aureginosa , 80.95% for RO concentrate against S. aureus , and 83.61% for RO-concentrate against P. aureginosa . When the antimicrobial activity of the extracted phenol from WGH and its different concentrate and permeate samples were evaluated by micro dilution and disk diffusion methods, it was found that the ability of the concentrate samples to inhibit bacterial growth was much higher than permeate ones. In addition, extracted phenol from WGH and its different concentrate and permeate samples showed significant DNA nuclease activity., Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05588-w., Competing Interests: Conflicts of interestThe authors declare that they have no competing interests., (© Association of Food Scientists & Technologists (India) 2022, Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Microplastics (MPs) pose potential public health challenges because of their widespread occurrences in all environmental compartments. While most studies have focused on the occurrence fate of microplastics in wastewater treatment systems, the biodegradation of microplastics in wastewater is generally little understood. Therefore, we used two Gram-positive and thermophilic bacteria, called strain ST3 and ST6, which were identified by morphological, biochemical, physiological, and molecular analyses, to assess the growth and biodegradation potential of two different sized (50 and 150 m) polyethylene particles. The degradation was monitored based on structural and surface morphological changes. According to 16S rRNA analyses, ST3 and ST6 were identified as Anoxybacillus flavithermus ST3 and Anoxybacillus sp. ST6, respectively. The occurrence of cracks, holes, and dimensional changes was detected by scanning electron microscopy. Moreover, critical characteristic absorption band formation and modifications were determined by Fourier transform infrared spectroscopy. In addition to these, it was found that Anoxybacillus flavithermus ST3 and Anoxybacillus sp. ST6 produced high level of alpha-Amylase. These results showed that thermophilic bacteria are capable of the biodegradation of microplastics and production of alpha-Amylase., Competing Interests: The authors declare no conflict of interest.

In this study, the electrooxidation (EO) and membrane processes were used for chemical oxygen demand (COD) and total phenol (TPh) removal from wet scrubber wastewater (WSW). EO experiments were carried out using Al, Fe, SS, Ti, graphite, active carbon cloth electrodes and Box-Behnken design were used for optimization of maximum COD and TPh removal efficiency. Moreover, membrane filtration experiments were conducted to EO process using nanofiltration (NF270) and reverse osmosis membranes (SW30 and BW30). The maximum COD (55%) and TPh (50%) removal efficiency was achieved at pH of 8, 150 A/m 2 current density, and 180 min reaction time in EO process. Membrane filtration results showed that COD removal efficiency was the highest for SW30 membrane (95.18%) compared to BW30 (91.15%) and NF270 (80.11%) membranes. TPh removal efficiency in the NF270, BW30, and SW30 membranes was 27.08%, 96.06%, and 98.02%, respectively. The effect of microbial cell viability of the raw and treated wet scrubber wastewater after electrooxidation and membrane filtration was also investigated using E. coli. In addition to these, biofilm inhibition of the raw wet scrubber wastewater and the treated WSW after EO and membrane filtration were tested and the highest biofilm inhibition was found as 76.43% and 72.58% against S. aureus and P. aeruginosa, respectively, in 1/20 diluted samples of the raw WSW. This study suggests that the integrated process using EO and pressure-driven membrane methods are an efficient strategy for COD and TPh removal from WSW., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Nanoflowers are a newly developed class of nanoparticles that show flower-like structures and attract much attention due to their simple preparation methods, high stability, and increased efficiency. The aim of the study is to investigate a strong alternative to reduce the severity of infection and increase the treatment of wastewater by exhibiting biofilm inhibition in medical and environmental applications of the ZnO-NFs with two different shapes. ZnO-NFs were synthesized by two different processes hydrothermal method (named ZnO-NF1) and the precipitation method (named ZnO-NF2). ZnO-NFs produced by two different synthesis methods were compared for the photocatalytic and antioxidant efficiency. The effects of Reactive Red 180 (RR180) and Basic Red 18 (BR18) dyes concentration, photocatalyst amount, and reaction time were investigated on dye removal efficiency for photocatalytic experiments. The color was completely removed for 25 mg/L BR18 and RR180 dyes for 75 min and 90 min, respectively, using 1.5 g/L photocatalyst amount using ZnO-NF1. However, 59.18% dye removal efficiency was obtained for 90 min by using a 1.5 g/L ZnO-NF2 photocatalyst for 25 mg/L BR18 dye removal, while a dye removal efficiency of 90.00% was detected for 90 min using 2 g/L ZnO-NF2 for 25 mg/L RR180 dye. Then, comparison of general properties such as antibacterial, antibiofilm, microbial cell viability, DNA fragmentation, antioxidant activities, and antimicrobial photodynamic therapy of ZnO-NFs were investigated. The antioxidant activity of ZnO-NF2 was found to be higher than ZnO-NF1 at each concentration (82.32% and 87.18% for ZnO-NF1 and ZnO-NF2, respectively, at 200 mg/mL)., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Fenton oxidation is an effective and valuable method for wastewater treatment. To inhibit environmental impacts and increase overall reaction efficiencies, it is important to develop advanced catalysts. This paper illustrates an experimental study on the elimination of RR180 dye from synthetic aqueous solutions with raw leonardite and different iron-loaded leonardite powders, Fe(0)-loaded leonardite, and Fe(II)-loaded leonardite. The effect of solution pH (2.0-6.0), catalyst amount (0.10-1.5 g/L), H 2 O 2 concentration (10-50 µL/L), and dye concentration (10-30 ppm) was tested to achieve maximum color removal efficiency using the three catalysts. At pH = 2, color removal efficiencies were higher and more suitable. Initial experiments showed the advantage of using Fe(II)-loaded leonardite on using Fe(0)-loaded leonardite. Fe(II)-loaded leonardite catalyst was the most efficient in RR180 color removal compared to the other tested reagents. Color removal in function of solution pH did not decrease much when Fe(II)-loaded leonardite was used (100 to 96%) when pH was increased from 2.0 to 6.0. In the other hand, dye removal has been significantly affected in the case of using raw leonardite, Fe(0)-loaded leonardite (93 to 0%), and (100 to 13%) in the same pH range, respectively. At optimum experimental conditions, catalyst amount: 0.75 g/L for Fe(II) and Fe(0)-loaded leonardite and 1.5 g/L for raw leonardite; dye concentration: 10 ppm; solution pH: 2.0; H 2 O 2 concentration: 50 µL/L; volume: 100 mL and reaction time: 60 min, RR180 dye removal efficiencies were 91%, 100%, and 100% by raw leonardite, Fe(0)-loaded leonardite and Fe(II)-loaded leonardite, respectively. The stability and reusability of the tested catalyst was investigated up to ten cycles. The experimental results revealed that both Fe(0)-loaded leonardite and Fe(II)-loaded leonardite can be used in Fenton reaction up to four cycles without decreasing their efficiency in RR180 color removal. The characterization of the catalysts was established using scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDX). The synthesized catalyst can be used at large scale in any textile industry to effectively remove dyes resulting in high elimination rates at the optimal determined and studied conditions., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study presents the effect of electro-oxidation and Fenton pre-treatment on anaerobic co-digestion (AnCoD) of fruit-juice industrial waste (FJW) and municipal sewage sludge (MSS). Biogas production increased from 767 mL to 857 mL and 918 mL after EO and Fenton pretreatment, respectively. The methane amount increased by 28% and 39% for EO and Fenton processes. The removal efficiencies of soluble COD, carbohydrate, and protein for the conditions with the highest biogas production as a result of the pretreatment process were 48%, 65%, 61% for the Fenton pre-treatment, and 37%, 52%, and 39% for the EO pre-treatment, respectively. Cumulative biogas production efficiency for all pre-treated mixtures was estimated with kinetic models. In addition, an evaluation has been made regarding cost, economic gain, and energy consumption of the pre-treatment processes., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

One of the most important problems affecting the environment today is the inability to adequately treat wastewater containing dyes. Among of the many treatment processes used in the treatment of dye-containing wastewater, photocatalytic based wastewater treatment processes attract the attention of scientists as a new, economically feasible, and promising approach which has been in practice for a few decades. However, in order to use these processes in wider areas, cheap and effective catalysts are still being developed today. In this study, the photocatalytic activity of eggshell-CaO produced from waste chicken eggshells was investigated for decolorization of Safranin (Basic Red 2) and Reactive Red 180 (RR180) dyes. First, sintering process was applied to the waste chicken eggshells at different temperatures (300, 600, 900 °C) in order to observe CaO formation from the eggshells. Second, the parameters such as photocatalyst amount, pH, concentration of dyes, and reaction time were optimized on dye removal efficiency in photocatalytic experiments. The optimum conditions were performed under visible light and found to be 1 g/L of catalyst amount (sintered at 900 °C), original solution pH (6.80 for Safranin and 6.60 for RR180), and 5 mg/L of dye concentration. The photocatalytic removal efficiencies of Safranin and RR180 dyes were 100% and 97.90%, respectively, under the determined optimum experimental conditions. The adsorption efficiency of the dyes that could be realized during the photocatalytic experiment was measured as 20.99% and 9.99% for Safranin and RR180 dyes, respectively., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In this study, hydrochar-based-eggshell was prepared via the subcritical water medium (SCWM) and used as a catalyst in the thermally activated peroxide oxidation (TAPO) approach for crystal violet and dye bathing wastewater degradation. The catalytic activities for the raw eggshell (RES) and hydrochar-based-eggshell (HES) were compared. RES and HES were characterized using a scanning electron microscope (SEM),energy-dispersive X-ray spectroscopy (SEM-EDX), and Fourier transforms infrared spectroscopy (FT-IR). The affecting parameters on the degradation process were optimized using response surface methodology (RSM). The effects of temperature (293-333 K), amount of catalyst (5-25 mg/50 mL), the concentration of H 2 O 2 (0-8 mM), and treatment time (10-70 min) on the TAPO method were investigated using central composite design (CCD). For the crystal violet removal, two models were developed. Both models were significant and can be used to describe the design space. Also, the dye bathing wastewater degradation was described by another developed model, which had a high correlation coefficient (R 2  = 0.97). In general, catalytic activity for HES was higher than RES. The degradation of crystal violet reached 98.10% when a 20 mg HES catalyst and 6 mM H 2 O 2 at 323 K for 55 min were used. While 97% of the color of dye bathing wastewater was removed in 55 min at 323 K using 25 mg of HES and 4 mM H 2 O 2 . This study showed that the hydrolyzed eggshells could be used in the oxidation of crystal violet and dye bathing wastewater by the thermally activated peroxide oxidation method., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this study, environmental-friendly composite polyethersulfone (PES) membranes based on basalt powder were prepared by phase inversion method. The effects of polymer percentage, the basalt percentage, and the thickness of the membrane were investigated on the distilled water flux, compaction factor, bovine serum albumin (BSA) rejection, contact angle, fouling factor and the parameters were modelled by response surface methodology (RSM). The distilled water flux increased when the basalt was added to the membrane up to 6% percentage of the polymer amount. The blending of basalt also provided resistance against the membrane compaction. The BSA rejection experiments approved the positive effects of basalt on the rejections efficiencies. At higher basalt percentages, the rejection efficiencies increased from 78% at the raw membrane to 99% for the composite membranes had 10% basalt. The adding of basalt to the membranes decreased the contact angles. The hydrophilicity of the membranes contained basalt in their structures was higher than those which had not basalt. By comparison with the neat membranes and the basalt added membrane, it can be said that the basalt increased the flux recovery and decreased the irreversible fouling factors. The basalt increased the antifouling properties for the composite membranes. Finally, the prepared membranes were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX).