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Dyeing industries release their hazardous dyeing effluents into the environment which affects the human health and ecosystem. Hence, the removal of dye from waste‐water is mandatory one. In this present study, focus on the fabrication of bio‐clay‐ceramic hybrid composites by dispersing bentonite (BT) clay and ceramic hydroxyapatite (HA) into alginate (Alg) and gelatin (Gel) polymeric matrixes by in‐situ method which gives BTHAAlg and BTHAGel hybrid composites for methylene blue (MB) removal. The various adsorption influencing parameters such as shaking time, adsorbent dosage, pH and initial MB concentration were optimized under batch method. The highest MB adsorption capacities of BTHAAlg and BTHAGel composites were found to be 43.70 and 47.50 mg/g respectively with optimized conditions of 100 mg/L of initial MB concentration, 40 min shaking time and 0.1 g dosages. In pH studies, the high MB adsorption capacity of bio‐clay‐ceramic composites were noticed at pH 11. The characterization techniques like FTIR, SEM and EDAX analysis were performed to find the physico‐chemical properties of bio‐clay‐ceramic composites. The equilibrium data of hybrid composites towards MB adsorption was well fitted with Langmuir isotherm model than D‐R and Fruendlich models because of higher r and low sd values. The negative values of ▵Go at three different temperatures (303, 313 and 323 K) indicate that the spontaneous nature of MB adsorption, while positive values of ΔHo and ΔSo revealed that the MB adsorption onto hybrid composites was endothermic in nature and more randomness occurred at solid/liquid interfaces. In kinetic studies, the MB adsorption onto hybrid composites was well fitted with pseudo‐second‐order and intra‐particle diffusion models. The electrostatic attraction and hydrogen bonding plays a dominant role in MB adsorption onto BTHAAlg and BTHAGel bio‐clay‐ceramic composites. The regeneration studies proposed that the hybrid composites can be reusable upto five cycles. Hence, the developed bio‐clay‐ceramic hybrid composites were act as best adsorbents for MB removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • MCGHCOF beads were prepared and used for fluoride adsorption studies. • MCGHCOF beads remove fluoride both in standard and field water. • MCGHCOF beads are regenerable and regenerated upto six cycles. • MCGHCOF beads are providing water with safe fluoride levels. The developed biocompatible materials like covalent organic frameworks (COFs) and hydroxyapatite acquire significant defluoridation capacity (DC). But because of their powder nature, creates column blockage, pressure drop during field investigations and difficult in separation after fluoride adsorption. To address these problems, COFs and hydroxyapatite were fabricated in the usable form of beads using chitosan, gelatin and iron oxide materials as magnetic chitosan–gelatin/hydroxyapatite/covalent organic frameworks (MCGHCOF) bio-beads were developed and it was potentially applied for the removal of fluoride from water. The MCGHCOF bio-beads surface and their properties were described with FTIR, EDAX, SEM and XRD analysis. The adsorption studies were performed under the batch method. The HCO 3 – ion has a vital inhibitory effect on DC and this may be because of the similar ionic size of fluoride and HCO 3 –. The enhanced DC of MCGHCOF beads was found to be 4992 mgF-.kg−1 in 30 min at pH 7. Isotherm experimental data of fluoride adsorption was apt with Langmuir isotherm than Fruendlich and D-R isotherm models. The defluoridation system is endothermic and its spontaneous nature was demonstrated with thermodynamic studies. Kinetic studies of experimental data of fluoride adsorption were well-fitted with pseudo-second-order and intraparticle diffusion. The complexation and electrostatic interaction play a predominant role in fluoride adsorption by MCGHCOF beads. The MCGHCOF bio-beads are stable and are reusable upto six cycles. The collected field water sample was examined using MCGHCOF beads and it reduced the fluoride concentration to the tolerable drinking water threshold as recommended by WHO (1.5 mg L−1). [ABSTRACT FROM AUTHOR]

• APMZ and CPMZ composite were employed for fluoride removal. • APMZ and CPMZ composite remove fluoride both in standard and field water. • APMZ and CPMZ composite remove fluoride via electrostatic interaction. • APMZ and CPMZ composite are regenerable and provide water with safe fluoride levels. Defluoridation acts a crucial role in supplying water with safe fluoride limits. The marvelous magnesia possesses noticeable defluoridation capacity (DC). However to make magnesia in usable composite form and to enhance the DC, the magnesia was dispersed with hybrid polymers (alginate and pectin) followed by cross-linked with zirconium ion namely APMZ composite and the magnesia was also dispersed with hybrid polysaccharide polymers (chitosan and pectin) followed by cross-linked with zirconium ion namely CPMZ composite was prepared for superior defluoridation studies. The synthesized APMZ and CPMZ composites possess superior defluoridation capacities (DCs) of 4983 and 4994 mgF− kg−1 respectively than pectin, magnesia and chitosan material. The influencing factors of fluoride adsorption was optimized and controlled in batch level. The surface properties of APMZ and CPMZ composites were examined with EDAX, SEM, XPS and FTIR studies. The investigational/equilibrium data of defluoridation by APMZ and CPMZ composites were correlated with different isotherms specifically Fruendlich, Langmuir and Dubnin-Radushkevich (D-R) models. In addition, order of fluoride adsorption rate was evaluated with kinetic experiments. The saturation point of thermodynamic factors indicates fluoride adsorption onto APMZ and CPMZ composites was endothermic with spontaneous nature. Moreover, the synthesized APMZ and CPMZ composites were effectively reutilized upto six cycles. The field investigation result shows that synthesized APMZ and CPMZ composites can be potentially utilized as fluoride removal from field contaminated water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon-based materials with high S BET (1355–1716 m2g−1) were fabricated from palm leaves. • Fast kinetic processes were obtained with 95 % saturation in less than 8 min. • Adsorbents presented high efficiency in treating simulated industrial effluents up to 98.38%. • DFT calculation elucidated the methylparaben uptake mechanism on the carbon materials. The emerging contaminant methylparaben was successfully removed from aqueous effluents using three carbon-based materials (BoCM-1, BoCM-2, and BoCM-3). These materials were prepared from the agro-waste Butia odorata (Bo), using the proportion of Bo: ZnCl 2 of 1:1 (BoCM-1), 1:2 (BoCM-2), and 1:3 (BoCM-3). Surface area, pore size distribution, total pore volume, FTIR, Boehm titration, CHN elemental analysis, TGA, HI, and pH pzc characterized these carbon-based materials. The kinetic data were best fitted using the fractal-like pseudo-first-order (FPFO) model to explore the adsorption of methylparaben on the three adsorbent materials. The kinetic studies also show that 95 % of the adsorbent saturation (t 0.95) adsorbent occurs < 8 min. The isotherm studies showed that the Liu isotherm model was the best to explore the adsorption results. The maximum values of Q max at 45 °C (Liu) were 637.7 (BoCM-1), 869.9 (BoCM-2), and 398.7 mg g−1 (BoCM-3). Using the nonlinear van't Hoff equation, the values of ΔH° values range from –22.82 to –33.27 kJ mol−1, suggesting the adsorption process is physical. Simulated industrial wastewater was tested to check the performance of the carbon materials for potential use for actual wastewater treatment, attaining a maximum removal of 98.38 % using BoCM-2 material. DFT calculations provide a molecular picture of the physisorption of methylparaben on carbon-based materials. [ABSTRACT FROM AUTHOR]

Heavy metals enter our environment through diverse resources, causing harmful effects owing to their inherent toxicity and facile migration into aqueous medium, becoming an environmental challenge. Among technologies able to remove these contaminants, the adsorption process emerges as a promising application for water treatment. Herein, functionalized silica magnetic nanoparticles using inorganic and organic have been employed as adsorbents to remove environmental hazards from wastewater effectively. Magnetic silicate core-shell amino-functionalized (Fe 3 O 4 @SiO 2 -AP) nanocomposites were synthesised using acrylic acid (AA) and para-aminobenzoic acid (PABA) as dual copolymer for Cd (II) removal. The characterization analysis confirmed the formed crystal nanostructure and the copolymers were chemically introduced in the magnetic silicate core-shell nanoparticle. The Cd (II) adsorption results on (Fe 3 O 4 @SiO 2 -AP) nanocomposites achieved an impressive q max of 32.50 mg/g at pH 8, adsorbent dosage of 3 g/L, and Cd (II) concentration of 100 ppm. The laboratory-scale fixed-bed column showed the breakthrough curves are flow rate independent, achieving metal removal of 99% for 405 min, at pH 8, influent ion concentration of 100 ppm, flow rate of 5 mL/min, and 1 cm bed height. The Freundlich model was the most suitable for fitting equilibrium data (R2 adj = 0.981) indicating a multi-layer adsorption phenomenon in the heterogeneous surface sites of the (Fe 3 O 4 @SiO 2 -AP) nanocomposites. The pseudo-second-order model (R2 adj =0.999) confirms that the adsorption rate depends on nanocomposites active sites and occurs by chemical sorption mechanism. The reusability adsorption-desorption experiments slightly decreased from 97.5 to 86.7% in the sixth cycle stability, demonstrating the material stability. [Display omitted] • Sustainable magnetic silicate core-shell amino-functionalised nanocomposites were synthesised. • Multi-layered adsorption by Cd(II)-nanoparticles complex interactions, breakthrough curves are independent of flow rate. • Fe 3 O 4 @SiO 2 -AP recovered by an external magnetic field-driven. • Adsorption was driven by hydrogen bonding and coordination bonds. • High material stability and reusability after the sixth cycle was achieved. [ABSTRACT FROM AUTHOR]

Docosahexaenoic acid (DHA) is a high-value polyunsaturated fatty acid. The industrial development of microbial DHA was restricted due to high medium cost. Kitchen wastewater was always rich in nitrogen, phosphorous, carbohydrates, which can be used for microorganism growth. This study developed of a primitive low-cost culture medium for a new isolated high-production DHA strain using kitchen wastewater. The results showed that, a total of 66 strains were isolated from mangrove habitats. The highest DHA-producing strain N6 was identified as Aurantiochytrium sp. (GenBank accession number OL455742) with a DHA production of 6.56 g/L. Then the optimization of kitchen wastewater medium was designed by Response Surface Methodology, and 7.14 ∼ 7.23 g/L of DHA production was obtained. At the same time, the lipid content in Aurantiochytrium sp. N6 was as high as 75.68%, which contributed to the increase of DHA production in optimal kitchen wastewater medium. Finally, the substrate cost of kitchen wastewater medium was reduced by 43.95%. Meanwhile, the dissolved organic carbon (DOC), dissolved nitrogen (DN) and dissolved phosphorus (DP) in kitchen wastewater were utilized by Aurantiochytrium sp. N6 more than 90%. This work enriched the competitive candidate DHA-producing microbes, and provided a perceptive idea for both the medium substrate cost reducing and kitchen wastewater recycling. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of biomass-based carbon materials has accelerated the research interest in environmental (e.g., adsorbents for wastewater decontamination) and energy applications (e.g., batteries). In this paper, we developed a series of carbon materials (CMs) using a sulfur doping strategy to improve the physicochemical, adsorptive and energy storage properties of the aforementioned CMs. CMs were prepared and optimized using an experimental design denoted as the Box-Behnken design approach with three independent factors (i.e., the temperature of pyrolysis, zinc chloride: biomass ratio and sulfur: biomass ratio), and the responses were evaluated, namely the Specific Surface Area (S BET), mesopore area (A Meso) and micropore area (A Micro) with the help of Nitrogen Physisorption. According to the statistical analysis, under the studied conditions, the responses were mainly influenced by the pyrolysis temperature and ZnCl 2 ratio, while the sulfur content did not give rise to any remarkable differences in the selected responses. The physicochemical characterization of the CMs suggested that very high Specific Surface Areas ranging from 1069 to 1925 m2 g−1 were obtained. The sulfur doping resulted in up to 7.33 wt% of sulfur in the CM structure, which yielded CMs with more defects and hydrophilic surfaces. When tested as adsorbents, CMs exhibited a very high adsorption capacity (190 – 356 mg g−1), and as anodes, they demonstrated a competitive Lithium Ion Battery (LIB) storage capacity, at least during the first five cycles (306 mAhg−1 at 1 C for CM9). However, further studies on long-term cyclability are required to prove the CM materials suitability in LIBs. This work extends our understanding of how pyrolysis and sulfur doping of biomass feedstock affects carbon materials' usability, final characteristics and potential to use in wastewater decontamination by adsorption and as anodes in LIBs. [Display omitted] [ABSTRACT FROM AUTHOR]

Over the last years, the strategy of employing inevitable organic waste and residue streams to produce valuable and greener materials for a wide range of applications has been proven an efficient and suitable approach. In this research, sulfur-doped porous biochar was produced through a single-step pyrolysis of birch waste tree in the presence of zinc chloride as chemical activator. The sulfur doping process led to a remarkable impact on the biochar structure. Moreover, it was shown that sulfur doping also had an important impact on sodium diclofenac (S-DCF) removal from aqueous solutions due to the introduction of S-functionalities on biochar surface. The adsorption experiments suggested that General and Liu models offered the best fit for the kinetic and equilibrium studies, respectively. The results showed that the kinetic was faster for the S-doped biochar while the maximum adsorption capacity values at 318 K were 564 mg g−1 (non-doped) and 693 mg g−1 (S-doped); highlighting the better affinity of S-doped biochar for the S-DCF molecule compared to non-doped biochar. The thermodynamic parameters (ΔH0, ΔS0, ΔG0) suggested that the S-DCF removal on both adsorbents was spontaneous, favourable, and endothermic. • Sustainable synthesis of sulfur-doped carbon with superior adsorptive properties. • High surface area Sulfur-doped carbon (1809 m2 g−1) with predominant mesoporosity. • Sulfur doping boosted diclofenac removal due to the number of S-functionalities. [ABSTRACT FROM AUTHOR]

• The pristine Co 3 O 4 is synthesized through a deep eutectic solvent (DES). • Polymer matrix is introduced by ball milling. • P3DDT-Co 3 O 4 exhibited higher specific capacitance (294F/g) at current density of 1 A/g. • P3DDT-Co 3 O 4 show higher cyclic stability (96%) over 5000 cycles. Transition metal oxide-based materials continue to attract interest in energy and environmental applications due to their unique characteristics. However, their integration with polymers needs to be explored to achieve enhanced capacitance values. To address this issue, two step strategy is utilized wherein the first step involves preparation of a pristine transition metal oxide (Co 3 O 4) by a deep eutectic solvent (DES) consisting of choline chloride and hydrogen donor ethyelene glycol in the ratio of 2:1. In the second step the environmentally friendly high energy ball milling is utilized with strong mechanical forces producing desired poly-3-dodecyl thiophene (P3DDT)-wrapped cobalt oxide (Co 3 O 4). The structural and morphological properties of the prepared Co 3 O 4 and its composite (P3DDT-Co 3 O 4) are determined by aid of X-ray diffraction (XRD) studies, Field emission scanning electron microscope (FESEM), and X-ray photoelectron spectroscopy (XPS). The synthesized Co 3 O 4 exhibited petal-like morphology, whereas in P3DDT-Co 3 O 4 the polymer appears to be completely wrapped on transition metal oxide. The electrochemical characteristics of electrodes were studied. The P3DDT-Co 3 O 4 exhibited higher specific capacitance (294F/g) than pristine Co 3 O 4 (174F/g) at a current density of 1 A/g and its retention capacity increased (96%) and then decreased (93%) over 5000 cycles in a three-electrode cell assembly. The lowest capacitance (136F/g) was obtained for P3DDT. Experimental results demonstrate that the design is suitable for upgrading favorably active electrochemical spots in Co 3 O 4 during the incorporation of P3DDT by the ball-milling procedure, showing outstanding performance in energy-storage applications. [ABSTRACT FROM AUTHOR]

The escalating consumer demand for crabs results in a growing amount of waste, including shells, claws, and other non-edible parts. The resulting crab shell waste (CSW) is disposed of via incineration or landfills which causes environmental pollution. CSW represents a potential biological resource that can be transformed into valuable resources via pyrolysis technique. In this study, microwave pyrolysis of CSW using self-purging, vacuum, and steam activation techniques was examined to determine the biochar production yield and its performance in treating palm oil mill effluent (POME). The biochar produced through microwave pyrolysis exhibits yields ranging from 50 to 61 wt%, showing a hard texture, low volatile matter content (≤34.1 wt%), and high fixed carbon content (≥58.3 wt%). The KOH-activated biochar demonstrated a surface area of up to 177 m2/g that is predominantly composed of mesopores, providing a good amount of adsorption sites for use as adsorbent. The biochar activated with steam removed 8.3 mg/g of BOD and 42 mg/g of COD from POME. The results demonstrate that microwave pyrolysis of CSW is a promising technology to produce high-quality biochar as an adsorbent for POME treatment. [Display omitted] • Different microwave pyrolysis methods are examined for biochar production. • Biochar is further microwave-activated via steam and KOH. • High yield of biochar and activated biochar is obtained. • These biochar show desirable adsorption efficiency of COD and BOD. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient and cost-effective adsorbent P-CNT3 for CIP removal was successfully synthesized using hydrothermal technique. • The maximum adsorption capacity (qm) to adsorb CIP using P-CNT3 composite was 28.6 mg/g. • Freundlich model is the predominant adsorption model fit best with the experimental data at 298 K. • The qe of P-CNT3 was more than two folds higher than raw pumice. • Adsorption mechanisms between P-CNT3 and CIP were elucidated in detail. A novel CNT-derived Pumice adsorbent (P-CNT3) was successfully synthesized as an efficient adsorbent for Ciprofloxacin (CIP) removal from aqueous solutions. In present study, P-CNT3 composite synthesized by hydrothermal technique was loaded with multiwalled carbon nanotube (CNT) using sonification to remove CIP antibiotic. P-CNT3 composite were characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses. Adsorption performance was studied by adjusting the pH, contact time, initial CIP concentration, temperature and adsorbent dosage in a batch reactor to obtain the maximum adsorption capacity (qm). The maximum adsorption capacity (qm) was achieved in 240 min at pH ≤ 5). The adsorption process of P-CNT3 followed the pseudo-first-order kinetic model (R2 = 0.989) and sips isotherm model (R2 = 0.991), and qm to adsorb CIP was 28.6 mg/g. The illustrated adsorption mechanism shows that hydrophobic interactions, electrostatic and non-electrostatic interactions, suggests CIP adsorption. Over the temperature range of 298–318 K, the thermodynamic parameters ΔG°, ΔS° and ΔH° were calculated. The adsorption reactions were shown to be spontaneous and endothermic. Furthermore, activation energy suggested a physisorption mechanism for P-CNT3. In addition, regeneration study shows that the P-CNT3 can be reused five times with excellent results in CIP adsorption. Based on these findings, P-CNT3 can be considered a feasible low-cost adsorbent for CIP removal. Hence, the prepared P-CNT3 composite can be used as an inexpensive and a promising adsorbent for the removal of other pharmaceutical compounds. [ABSTRACT FROM AUTHOR]

Textile dyes are one of the most commonly found pollutants in water, and it is necessary to remove them before textile industry effluents are released into the environment. In this study, cellulose-based adsorbents were prepared by grafting N1-(3-trimethoxysilylpropyl)-diethylenetriamine (TMSPDETA) on microcrystalline cellulose surface for the adsorption of reactive dyes from aqueous solution. Characterization of the produced adsorbents [Cel@TMSPDETA 10 ; composite of cellulose + TMSPDETA (10% weight)] and the experimental and modeling studies were thoroughly investigated. Based on ΔBIC analysis (Bayesian Information Criterion), the fractal-like pseudo-first-order model (FPFO) was the model with the highest degree of adequacy to describe the kinetic behavior for RR-35 (Reactive Red 35) and RG-19 (Reactive Green 19) dye adsorption on Cel@TMSPDETA 10. It was observed that the values of t 0.95 (time necessary to attain 95% saturation) of RG-19 dye were 1.81 times slower than those of RR-35. This difference in times to attain 95% saturation of RG-19 with RR-35 could be assigned to the larger size of the RG-19 molecule. Based on the ΔBIC values, the Liu isotherm was better fitted to the experimental data. At 30 °C, the highest Q max (Liu model) value was 197.0 mg g−1 for RR-35 dye. For RG-19, the highest value of Q max (Liu model) was 210.5 mg g−1 at 45 °C. Alternatively, a statistical physics model that represents the general case of the Langmuir model was adopted to provide new insights into the adsorption mechanisms of RR-35 and RG-19 dyes on the adsorbents. Interestingly, this new approach showed that RR- 35 was adsorbed via a partial aggregation process, contrary to the RG-19 dyes. [Display omitted] • Increase in the sorption capacity of up to 8 times Cel@TMSPDETA 10 to Cel • Cel@TMSPDETA 10 was employed to remove RR-35 and RG-19 dyes from wastewater. • The FPFO and Liu models were fitted to describe the kinetic and equilibrium experiments. • Statistical physics data shows that RR-35 was adsorbed with a lower aggregation degree. • Statistical physics data shows that RG-19 was adsorbed with a higher aggregation degree. [ABSTRACT FROM AUTHOR]

[Display omitted] • Experimental data shows that GO·Fe 3 O 4 1:1 demonstrates the highest adsorption capacity. • The amount of magnetite incorporated has an influence on the adsorption behavior. • The GO·Fe 3 O 4 1:1 proves to be efficient for effective removal of ZPD from aqueous solutions. • The magnetic nanocomposite showed excellent reuse and easy operation, eliminating subsequent centrifugation/filtration steps. This study evaluated the adsorption of zolpidem (ZPD) on magnetic graphene oxide (GO‧Fe 3 O 4). The graphene oxide-based magnetic adsorbents used to remove zolpidem were synthesized with different amounts of magnetite. The Adsorbents were characterized, confirming the presence of magnetic nanoparticles on the graphene oxide surface. The best magnetic nanoadsorbent was GO‧Fe 3 O 4 1:1, with a removal percentage of 87.07 % at pH 5.0 and 293.15 K. In this sense, zolpidem removal was unrelated to the graphene oxide surface area but to the surface chemistry of the adsorbent. The physical–chemical Interactions between the ZPD molecules and the functional groups of the adsorbent were suggested. ZPD adsorption on GO‧Fe 3 O 4 1:1 was spontaneous and exothermic. The equilibrium and kinetic studies (Sips and Elovich) suggested adsorption in a heterogeneous surface. Furthermore, the adsorbent presented excellent adsorption efficiency even after many regeneration cycles, and magnetic behavior avoids the centrifugation/filtration steps. Until now, no study in the literature reported removing this harmful and widespread hypnotic drug from water contamination, and GO·Fe 3 O 4 1:1 was an efficient nanomaterial to remove ZPD from aqueous solutions. [ABSTRACT FROM AUTHOR]