Adsorption study of heavy metal ions from aqueous solution by nanoparticle of wild herbs

Wild herbs (Equisetum, EH and Teucrium, TH) were used as environment friendly adsorbents in the present study. This study focuses on the investigation of the adsorption ability of Co, Cd and Li from aqueous solution. The adsorption of heavy metals onto EH and TH was dependent on particle size, dose, solution pH, contact time, and temperature. Kinetic data were tested using pseudo-first-order and pseudo-second-order kinetic models. The best fit was obtained with the pseudo-second-order kinetic model. Langmuir and Freundlich models have been applied to calculate adsorption data and the thermodynamic parameters; entropy, ΔS°, enthalpy, ΔH°, and the Gibbs free energy, ΔG°; were determined. The results suggests that the adsorption of heavy metals by the wild herbs are endothermic and a spontaneous process. Thus, it was concluded that EH and TH are promising adsorbents for the adsorption of heavy metals from aqueous solutions. Keywords: Wild herbs, Heavy metal, Equisetum, Teucrium, Adsorptio

Biosynthesis Effect of Egg White on Formation and Characteristics of NiO/NiCo₂O₄ Nanocomposites

For the successful production of NiO/NiCo2O4 nanocomposites, the environmentally friendly method of egg white supplementation has been used. Several analytical techniques were employed to characterize the morphology, purity, and crystal structure of the as-prepared nanocomposites. These techniques included transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The physical adsorption and magnetic properties of the investigated composite were determined using the Brunauer–Emmett–Teller (BET) method and a vibrating-sample magnetometer (VSM), respectively. The results have shown that the as-prepared composite particles had diameters of about 10–25 nm, with uniform distribution. The XRD analysis showed that the as-synthesized composites consisted entirely of cubic structures of both NiO and spinel NiCo2O4 nanoparticles, with a space group of Fd3m. The FTIR analysis showed characteristic vibration modes related to metal oxides, confirming the formation of composites containing NiO and NiCo2O4 crystallites. The investigated composites’ saturation magnetization (MS) and coercivity (HC) were easily controllable because of the ingredients’ ferromagnetic (NiCo2O4) and antiferromagnetic (NiO) characteristics. The excellent combination of the NiO/NiCo2O4 nanocomposites’ properties is anticipated to make this system suitable for a wide range of applications

Biosynthesis, Physicochemical and Magnetic Properties of Inverse Spinel Nickel Ferrite System

Nanosized Ni ferrite has been prepared by an ecofriendly green synthesis approach based on the self-combustion method. In this route, the egg white as a green fuel was employed with two different amounts (3 and 10 mL). The XRD results display the formation of a stoichiometric NiFe2O4-type inverse spinel structure with a lattice parameter located at 0.8284 nm and 0.8322 nm. Additionally, the nickel ferrites’ typical crystallite size, as synthesized, ranged between 4 and 18 nm. Indicating the development of ferrite material, FTIR analysis shows two distinctive vibrational modes around 600 cm−1 and 400 cm−1. TEM measurements show the formation of nanosized particles with semispherical-type structure and some agglomerations. As the egg white concentration rises, the surface area, total pore volume, and mean pore radius of the material, as prepared, all decrease, and according to the surface area parameters discovered using BET analysis. Based on VSM analysis, the values of saturation magnetization are 6.6589 emu/g and 37.727 emu/g, whereas the coercivity are 159.15 G and 113.74 G. The as-synthesized Ni ferrites fit into the pseudo-single domain predicated by the squareness values (0.1526 and 0.1824). It is mentioned that increasing the egg white content would promote the magnetization of NiFe2O4

Magnetic Behavior of Virgin and Lithiated NiFe₂O₄ Nanoparticles

A series of virgin and lithia-doped Ni ferrites was synthesized using egg-white-mediated combustion. Characterization of the investigated ferrites was performed using several techniques, specifically, X-ray Powder Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and High-resolution transmission electron microscopy (HRTEM). XRD-based structural parameters were determined. A closer look at these characteristics reveals that lithia doping enhanced the nickel ferrite lattice constant (a), unit cell volume (V), stress (ε), microstrain (σ), and dislocation density (δ). It also enhanced the separation between magnetic ions (LA and LB), ionic radii (rA, rB), and bond lengths (A-O and B-O) between tetrahedral (A) and octahedral (B) locations. Furthermore, it enhanced the X-ray density (Dx) and crystallite size (d) of random spinel nickel ferrite displaying opposing patterns of behavior. FTIR-based functional groups of random spinel nickel ferrite were determined. HRTEM-based morphological properties of the synthesized ferrite were investigated. These characteristics of NiFe2O4 particles, such as their size, shape, and crystallinity, demonstrate that these manufactured particles are present at the nanoscale and that lithia doping caused shape modification of the particles. Additionally, the prepared ferrite’s surface area and total pore volume marginally increased after being treated with lithia, depending on the visibility of the grain boundaries. Last, but not least, as the dopant content was increased through a variety of methods, the magnetization of virgin nickel ferrite fell with a corresponding increase in coercivity. Uniaxial anisotropy, rather than cubic anisotropy, and antisite and cation excess defects developed in virgin and lithia-doped nickel ferrites because the squareness ratio (Mr/Ms) was less than 0.5. Small squareness values strongly recommend using the assessed ferrites in high-frequency applications

Biosynthesis, Physicochemical and Magnetic Properties of Inverse Spinel Nickel Ferrite System

Nanosized Ni ferrite has been prepared by an ecofriendly green synthesis approach based on the self-combustion method. In this route, the egg white as a green fuel was employed with two different amounts (3 and 10 mL). The XRD results display the formation of a stoichiometric NiFe2O4-type inverse spinel structure with a lattice parameter located at 0.8284 nm and 0.8322 nm. Additionally, the nickel ferrites’ typical crystallite size, as synthesized, ranged between 4 and 18 nm. Indicating the development of ferrite material, FTIR analysis shows two distinctive vibrational modes around 600 cm−1 and 400 cm−1. TEM measurements show the formation of nanosized particles with semispherical-type structure and some agglomerations. As the egg white concentration rises, the surface area, total pore volume, and mean pore radius of the material, as prepared, all decrease, and according to the surface area parameters discovered using BET analysis. Based on VSM analysis, the values of saturation magnetization are 6.6589 emu/g and 37.727 emu/g, whereas the coercivity are 159.15 G and 113.74 G. The as-synthesized Ni ferrites fit into the pseudo-single domain predicated by the squareness values (0.1526 and 0.1824). It is mentioned that increasing the egg white content would promote the magnetization of NiFe2O4

Adsorption Potential of Schizophyllum commune White Rot Fungus for Degradation of Reactive Dye and Condition Optimization: A Thermodynamic and Kinetic Study

The pollution due to dyes from textile sector is one of the major issues faced worldwide. This study was focused on the removal of the reactive dye, Drimaren Turquoise CL-B using Schizophyllum commune, a white rot fungus (WRF) keeping in mind the current environmental conditions. Different parameters like pH, sources of carbon & nitrogen, temperature, concentration of dye and C/N ratio were used to investigate their effect on the process. Maximum dye removal of 95.45% was obtained at pH 4.5, temperature 35°C, inoculum size 3 mL, veratryl alcohol (mediator), glucose (carbon source) and ammonium nitrate (nitrogen source). The enzyme activity was determined by employing enzyme assay. Laccase and Lignin peroxidase (LiP) activity was low while Manganese peroxidase (MnP) activity was highest. Maximum bio-sorption was achieved at pH 1 and 313 K. The pseudo-2nd-order kinetic model & Freundlich isotherm was best suited for the process of removal of dye. From these data, it is concluded that white rot fungus could possibly be the excellent biomaterial for elimination of synthetic dyes from wastewater

Removal of Cr(III) from Aqueous Solution Using Labeo rohita Chitosan-Based Composite

This study focusses on the synthesis of chitosan-cellulose composite membrane derived from Labeo rohita fish scales (FS) for the removal of Cr(III) from aqueous solution, while chromium is a serious threat to groundwater. Waste FS are valorized to chitosan by demineralization, deproteination, and deacetylation successively. Cellulose was extracted from sugarcane bagasse using acidic hydrolysis. Chitosan-based cellulose composite porous membrane was fabricated by evaporating solvent from polymer solution in petri dish. The impact of pH, contact time, and absorbent dosage on the removal of Cr(III) from an aqueous solution was investigated. Atomic absorption spectrophotometer was used to check the Cr(III). Results showed that chitosan comprising 85% degree of deacetylation was achieved by alkali treatment, while yield was 22%. FTIR analysis confirmed the chitosan and chitosan-cellulose-based composite membrane. Morphology studies showed that the cellulose was strongly staggered and due to the chitosan, the surface of cellulose became rougher, which is good to enhance the adsorption capacity. The maximum removal 57% of Cr(III) from aqueous solution was observed at pH 6 at 60 min and 50 mg dosage of adsorbent. The minimum removal (47%) of Cr (III) was found at pH 2. These results confer that Labeo rohita-based chitosan-cellulose composite membrane has great potential for the removal of metals from industrial effluents

Mn2+ Doped Cobalt Oxide and Its Composite with Carbon Nanotubes for Adsorption-Assisted Photocatalytic Applications

In this study, cobalt oxide (Co3O4), Mn-doped Co3O4 (MDCO), and Mn-doped Co3O4-functionalized carbon nanotube (MDCO-CNTs) were synthesized via the co-precipitation method using cobalt nitrate and manganese nitrate as a cobalt and manganese precursor, respectively. Synthesized materials were assessed using different characterization techniques like scanning electron microscopy, X-ray diffraction, and UV-visible spectroscopy. Congo red in an aqueous solution was adopted as the model dye to estimate the adsorption-assisted photocatalytic efficiency of the synthesized materials. The samples studied for adsorpsstion-assisted photocatalysis were found to be highly effective and among all the samples, the best removal performance (80%) was obtained by treating the MDCO-CNTs composite for 50 min at 50 °C. Mathematical modeling shows that all of the samples followed a pseudo-second-order kinetic model and data best fitted to a Langmuir isotherm, implying that the process involved in the removal of Congo red dye is chemisorption

Mn²⁺ Doped Cobalt Oxide and Its Composite with Carbon Nanotubes for Adsorption-Assisted Photocatalytic Applications

In this study, cobalt oxide (Co3O4), Mn-doped Co3O4 (MDCO), and Mn-doped Co3O4-functionalized carbon nanotube (MDCO-CNTs) were synthesized via the co-precipitation method using cobalt nitrate and manganese nitrate as a cobalt and manganese precursor, respectively. Synthesized materials were assessed using different characterization techniques like scanning electron microscopy, X-ray diffraction, and UV-visible spectroscopy. Congo red in an aqueous solution was adopted as the model dye to estimate the adsorption-assisted photocatalytic efficiency of the synthesized materials. The samples studied for adsorpsstion-assisted photocatalysis were found to be highly effective and among all the samples, the best removal performance (80%) was obtained by treating the MDCO-CNTs composite for 50 min at 50 °C. Mathematical modeling shows that all of the samples followed a pseudo-second-order kinetic model and data best fitted to a Langmuir isotherm, implying that the process involved in the removal of Congo red dye is chemisorption

Fabrication of novel oxochalcogens halides of manganese and tin nanocomposites as highly efficient photocatalysts for dye degradation and excellent antimicrobial activity

The dark brown and white crystals of manganese and tin (Mn2Se3Cl2O7 and SnSe3O4Cl) have been synthesized by solid-state reaction at 450 C. The morphology and the elemental analysis of newly synthesized compounds were studied by SEM and EDX Analysis. SEM analysis reveals that the particle size for Mn2Se3Cl2O7 was found to be 0.2–2.5 μm and for SnSe3O4Cl 2.0–6.0 μm. The EDX studies showed the presence of Mn, Se, O, Cl, and Sn elements. Powdered XRD confirmed the presence of a new phase present in these compounds. Under UV-vis irradiation, the kinetics of methylene blue (MB) degradation catalyzed by produced nanoparticles were monitored. The dye degradation efficiency was estimated, and results reveals that after 150 min of irradiation, almost 75% of the dye was degraded in the presence of Mn compound while 71% degradation was shown by Sn compound. Both composites display antimicrobial activity against Staphylococcus aureus and Escherichia coli with a maximum value of 34.5 mm. The maximum antimicrobial activity shown by Mn-incorporated nanocomposites estimated at 32.5 mm was against Gram-positive bacteria and 26.4 mm against Gram-negative bacteria. Similarly, the maximum antifungal activity shown by Sn incorporated estimated at 33.9 mm was compared to Gram-positive bacteria and 27.8 mm against Gram-negative bacteria