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Adsorption is often considered to be the most competent and investigated treatment technique among wastewater technologies. The purpose of sequestration from wastewater is not validated through preferred utilization of costly starting material which pave way for the development of low-cost adsorbents. This review asserts the augmentation of both economically and environmentally sound sorbent material. The review encompasses gathering information from the literature insights dispersed over decades for the remediation of toxic pollutants especially dyes and heavy metals by various categories of adsorbents. Additionally, this review highlighted the adsorption of various emerging contaminants and pharmaceuticals. The review targeted to showcase various categories of adsorbent that can be refashioned and efficiently employed toward water treatment process. The review outlines and purposes the classification of diverse adsorbents involved in water treatment. Various Isotherm models and kinetic models employed in adsorption were also discussed. Mechanism of removal of pollutants was also outlined. The process of desorption gives the regeneration and recovery possibility of adsorbent providing opportunity of waste minimization, reusing it repeatedly was also reviewed here. Lastly, the significance of review and the future perspective for further adsorbent advancement were also detailed out. Hence, this review sufficiently authorizes the various adsorbent conceivability toward water treatment. [ABSTRACT FROM AUTHOR]

Over the last few decades, antifouling, protein rejection, and oil-water separations have become a challenge to technologists and environmentalists. In view of this, the proposed work reports formulation, characterization of facile hydrophilic chitosan-graphene oxide modified sustainable non-woven fabric-based sieve membranes (NWF@Cs/Gx) along with their application for antifouling, protein rejection, and multigrade oil-water emulsions separation studies. The surface morphology, diameter size of the fibers, and elemental analysis of the same were characterized with high-resolution microscopes (SEM), EDAX, and spectroscopically. The hydrophilicity of these membranes was investigated using contact angle and water uptake studies that exhibited pure water flux up to 165 L.m−2.h−1. These studies further confirmed the multigrade oil/water emulsions separation with 98% efficiency and more than 96% protein (Bovine Serum Albumin) rejection. These studies suggest that the formulated membranes may find application in the field of environmental, biological, and petroleum-based industries. [Display omitted] • Cs and GO modified NWF as hydrophilic sustainable sieve membranes (NWF@Cs/Gx). • Presence of GO nanosheets in NWF@Cs enhanced the hydrophilic activity of membrane. • NWF@Cs/Gx membranes exhibit pH responsive chemical stability. • Membranes concurrently exhibit rejection of BSA and multigrade oil-water separation. [ABSTRACT FROM AUTHOR]

The study focuses on fabrication of a cost‐effective Zinc Oxide nanoparticles (ZnONPs) adsorbent using Syngonium podophyllum leaves extract to remove hexavalent chromium (Cr6+) from synthetically prepared wastewater. Various spectroscopic techniques, including X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray analysis (EDX), and transmission electron microscopy (TEM), were used to characterize the ZnONPs. Fourier infra‐red spectroscopy (FTIR) detected that various organic compounds like flavonoids, terpenoids, and carboxylic acids acts as stabilizing and capping agent. The batch adsorption study was conducted to investigate the effects of Cr6+ adsorption time, pH, adsorbent concentration, and initial adsorbate concentration. The maximum adsorption capacity was 267.068 mg/g at 313 K. The Freundlich isotherm model was most suitable, indicating multilayer confiscation of Cr6+ on the heterogeneous surface. Chemisorption was identified as the mechanism of sequestration. Thermodynamic studies revealed that Cr6+ removal was spontaneous and feasible, with ΔG° values suggesting predominantly physisorption. Additionally, ZnONPs displayed strong antibacterial activity against S. aureus bacteria, making them a potential alternative to antibiotics. ZnONPs exhibited impressive antioxidant activity. Overall, ZnONPs synthesized through biosynthesis proved to be excellent nano‐sorbents, antioxidants, and biocompatible materials with promising applications in water remediation and healthcare. [ABSTRACT FROM AUTHOR]

This study defined a facile, inexpensive, and benign method to fabricate silver nanoparticles (AgNPs) using Tradescantia pallidum var. purpurea aqueous leaves extract for the first time. A UV–vis spectrum showed that the evaluated extract was promising for green synthesis of the SNP, with the highest peak of absorption between 450 and 550 nm. The phytochemicals present in the plant extract acts as capping and stabilization agent were confirmed by FTIR analysis. EDX proved the presence of Ag while SEM confirmed the AgNPs with the spherical shape. TEM revealed the average particle size was 23 nm. Additionally, AgNPs exhibited significant antibacterial activity and turbidimetry analysis showed MIC and MBC was in range of 25–100 µg/mL against both Gram positive and Gram-negative bacteria in Luria Bertani broth cultures. The AgNPs exhibited potent antibacterial activity against gram-positive bacteria, with a ZOI of 12 ± 0.25 mm produced against BacillusB subtilis showed the largest zones of inhibition, which were greater than the positive control (cefotaxime). The MIC values were 50 µg/mL for Pseudomonas aeruginosa, 25 µg/mL for Staphylococcus aureus and Escherichia coli, and 100 µg/mL for B. subtilis, confirming their significant antibacterial action. AgNPs inhibited the DDPH free radical scavenging activity with an IC50 = 91.87 µg/mL. It is believed that these AgNPs play a crucial role in determining the therapeutic potential of T. pallida due to their biological efficacy. [ABSTRACT FROM AUTHOR]

Sustainable resource-based oleo-polyurethanes with low viscosity, superior fluidity, and good ability to spread on the surface of the substrate without involving any organic solvents, led to the formulation of volatile organic compounds (VOCs) free polymer coatings. Here, work reports the use of Pithecellobium Dulce seed oil (PDO), an eco-friendly, abundantly available, and sustainable resource for the synthesis of oleo-polyurethane (PDPU) and formulation of its nanocomposites coatings. To enhance their physicomechanical, anticorrosive, and antimicrobial properties, the tungsten oxide (WO), polythiophene (PTH), and polythiophene enveloped tungsten oxide (PTH/WO) hybrid nanofillers were dispersed in the proposed oleo-PDPU matrix. The physicochemical properties of PDPU and their nanocomposites along with the physicomechanical characterization of their coatings were conducted using standard laboratory/American Standard Testing Methods (ASTMs), spectroscopic methods (FTIR, XRD, NMR), microscopic techniques (SEM and TEM), and thermo-gravimetric analysis (TGA) techniques were used for structural, morphological, and thermal characterization. Their corrosion protective performances were analyzed using salt mist chamber, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). Their microbial resistance performance against the S. aureus , E. coli , and P. aeruginosa bacteria was also investigated using the well diffusion method. These studies revealed that the hybrid nanofillers (PTH/WO) dispersed PDPU coatings possess highest antibacterial and anticorrosive activity as compared to plain PDO-based polyurethanes (PDPU) and other such systems reported in the literature. [Display omitted] • Sustainable Pithecellobium Dulce Seed Oil (PDO) polyurethane • A novel hybrid PTH/WO nanofiller dispersed PDPU nanocomposites. • Physico-mechanically advanced PTH-PDPU and PTH/WO-PDPU nanocomposite coatings. • Potentially innovative anticorrosive and antimicrobial bi-functional nanocomposite coatings [ABSTRACT FROM AUTHOR]

Herein, a magnetic biochar adsorbent based on Pyrus pyrifolia discarded peels impregnated with precursor FeCl3·6H2O was fabricated and probed as a low-cost adsorbent for toxic cationic dye methylene blue (MB). The textural characterization of Pyrus pyrifolia magnetic biochar (PMBC) obtained from BET analysis exhibited its mesoporous nature with SBET of 133.960 m2/g. The physicochemical characteristics of PMBC were elucidated using XRD, FTIR, SEM-EDX and TEM techniques. The impregnation of FeCl3 has a significant impact on the microstructure of Pyrus pyrifolia based biochar which resulted in enhancement in adsorption efficiency of PMBC. The sorption parameters adsorbent dosage, time, initial MB concentration, and pH were thoroughly elucidated using a batch methodology which were found to be 0.8 g/L, 40 min, 90 mg/L and 6, respectively. Temkin and pseudo-second-order rate equation respectively appropriated the equilibrium data than the rest of the models. The maximum adsorption capacity determined by the Langmuir model was found to be 967.80 mg/g. The adsorbent exhibited better regeneration up to 3 cycles validating its practical usage. The facile synthesis, economic, and environmentally benign characteristic of Pyrus pyrifolia magnetic biochar corroborated it as a highly efficient adsorbent to sequester MB from an aqueous phase. Pyrus pyrifolia discarded peels impregnated with FeCl3·6H2O were exploited as a novel magnetic biosorbent for the abatement of cationic dye from wastewater. The impact of operative variables was analyzed using batch methodology. Isotherm and kinetic modeling on equilibrium data was executed via non-linear approach which is very reliable in comparison to linear way. [ABSTRACT FROM AUTHOR]

In this research work Reduced Graphene Oxide with Nickel (II) peroxide/copper (I) Oxide (Gr@NiO 2 /Cu 2 O NCs) have been successfully synthesized through a facile, one-step green synthesis mediated through the honey. The benefit of this methodology is that both the reducing agents themselves and also the oxidized product are eco-friendly. Additionally, reduction capability to graphene oxide, the oxidized products of honey i.e. reducing sugar could also act as capping agent and stabilizer in the synthesis of Gr@NiO 2 /Cu 2 O NCs, which showed good stability as a heterogeneous catalyst. This environmentally friendly approach can open up the new possible synthesis route for the graphene based nanocomposites on industrial scale production. Moreover, In this context, herein we report, an easy and effective synthesis of substituted Schiff base derivatives through the Graphene-based (Gr@NiO 2 /Cu 2 O NCs) green heterogeneous catalyst under ligand-free conditions, which provided good to excellent yields. The catalyst was characterized by FT-IR, XRD, SEM-EDX, TEM, RAMAN, UV and DLS analysis. The thermal stability of the catalyst was assessed by TGA and DSC analysis. Shorter reaction times, low packing of catalyst and higher yields are the benefit of this novel protocol. Its activity and simple recyclability without losing catalytic activity sort this catalyst a better replacement than another catalyst. [ABSTRACT FROM AUTHOR]

Here, we present an innovative and creative sustainable technique for the fabrication of titania (TiO2) using Acorus calamus (A. calamus) leaf extract as a new biogenic source, as well as a capping and reducing agent. The optical, structural, morphological, surface, and thermal characteristics of biosynthesized nanoparticles were investigated using UV, FTIR, SEM, DLS, BET, and TGA-DSC analysis. The phase formation and presence of nanocrystalline TiO2 were revealed by the XRD pattern. FTIR analysis revealed conjugation, as well as the presence of Ti–O and O–H vibrational bands. The nanoparticles were noticed to be globular, with an average size of 15–40 nm, according to the morphological analysis, and the impact of size quantification was also investigated using DLS. The photocatalytic activity of bare, commercial P-25 and biosynthesized TiO2 (G-TiO2) nanoparticles in aqueous solution of rhodamine B (RhB) dye was investigated under visible light irradiation at different time intervals. The biosynthesized TiO2 nanoparticles exhibited strong photocatalytic activity, degrading 96.59% of the RhB dye. Different kinetic representations were utilized to analyze equilibrium details. The pseudo-first-order reaction was best suited with equilibrium rate constant (K1) and regression coefficients (R2) values 3.72 × 10−4 and 0.99, respectively. The antimicrobial efficacy of the prepared nanoparticles was investigated using the disc diffusion technique. Further, biosynthesized TiO2 showed excellent antimicrobial activity against the selected gram-positive staining (B. subtilis, S. aureus) over gram-negative (P. aeruginosa, E. coli) pathogenic bacteria in comparison to bare TiO2. [ABSTRACT FROM AUTHOR]

Here, we report the fabrication of nZVI by the wet chemical technique in the presence of ethanol using ferric iron and sodium borohydride as the reducing agents under ambient conditions. The obtained nZVI particles are mainly in a zero-valent oxidation state and do not undergo significant oxidation for several weeks. The structural and morphological parameters of nZVI were investigated by using UV, XRD, SEM, EDX, TEM, and DLS analysis. The optical nature, bandgap energy, and absorption edge were all revealed by the UV–visible spectrum. The phase development and crystallinity of nZVI particles were shown by the XRD pattern. The morphological investigation revealed that the nanoparticles were spherical with an average size of 34–110 nm by using ImageJ software, and the elemental analysis was analyzed using EDX. Furthermore, the catalytic treatment performance of domestic wastewater was evaluated in terms of pH, COD (chemical oxygen demand) solubilization, total solids (TS), volatile solids (VS), phosphorous, and total nitrogen (TN) reduction under aerobic and anaerobic operating conditions. The effluent was subjected to a process evaluation with a different range (100–500 mg/L) of nZVI dosages. The COD solubilization and suspended solids reduction were significantly improved in the anaerobic condition in comparison to the aerobic condition. Furthermore, the effect of nZVI on phosphorous (PO43−) reduction was enhanced by the electrons of iron ions. The high concentration of nZVI dosing has a positive impact on COD solubilization and phosphorous removal regardless of the aeration condition with 400 mg/L of nZVI dosage. [ABSTRACT FROM AUTHOR]

In this study, we aimed to observe how different operating parameters influenced the photocatalytic degradation of rhodamine B (RhB, cationic dye) and bromophenol Blue (BPB, anionic dye) over ZnO/CuO under visible light irradiation. This further corroborated the optimization study employing the response surface methodology (RSM) based on central composite design (CCD). The synthesis of the ZnO/CuO nanocomposite was carried out using the co-precipitation method. The synthesized samples were characterized via the XRD, FT-IR, FE-SEM, Raman, and BET techniques. The characterization revealed that the nanostructured ZnO/CuO formulation showed the highest surface area (83.13 m2·g−1). Its surface area was much higher than that of pure ZnO and CuO, thereby inheriting the highest photocatalytic activity. To substantiate this photocatalytic action, the investigative analysis was carried out at room temperature, associating first-order kinetics at a rate constant of 0.0464 min−1 for BPB and 0.07091 min−1 for RhB. We examined and assessed the binary interactions of the catalyst dosage, concentration of dye, and irradiation time. The suggested equation, with a high regression R2 value of 0.99701 for BPB and 0.9977 for RhB, accurately matched the experimental results. Through ANOVA we found that the most relevant individual parameter was the irradiation time, followed by catalyst dose and dye concentration. In a validation experiment, RSM based on CCD was found to be suitable for the optimization of the photocatalytic degradation of BPB and RhB over ZnO/CuO photocatalysts, with 98% degradation efficiency. [ABSTRACT FROM AUTHOR]