Statistical analysis of Litchi chinensis’s adsorption behavior toward Cr(VI)

Abstract The adsorption results of Cr(VI) removal from aqueous solutions on Litchi chinensis have been optimized by the Box–Behnken design of response surface methodology. Three experimental parameters (dose, temperature, and pH) were chosen as independent variables. The maximum Cr(VI) adsorption was obtained at the initial pH of 2. Analysis of variance (ANOVA) of the results was successfully used to check the significance of the independent variables and their interactions. The three-dimensional (3D) response surface plots were used to study the interactive effects of the independent variables on % Cr(VI) removal. These figures successfully interpret the effect of interaction between pH (0.1–1.0), adsorbent dose (0.1–1.0 g.) and temperature (0–50 °C). The second-order polynomial equation was generated for the response. A statistical hypothesis test was conducted to critically analyze the experimental data by applying t test, paired t test, and Chi-square test. The comparison of t-calculated and t-tabulated values showed that the results were in favour of the conducted experiment

Eco-Friendly Synthesis of Copper Nanoparticles from Fiber of Trapa natans L. Shells and Their Impregnation Onto Polyamide-12 for Environmental Applications

In this study, copper nanoparticles were synthesized from Trapa natans L. shells and loaded within polyamide-12 for use as an adsorbent. The synthesized nanocomposite was used for the first time to remove toxic methyl orange and brilliant green dye molecules from synthetic aqueous solutions. In order to characterize the plant-based nanocomposite, its functional groups, surface texture, elemental composition, structure, surface area, and crystallinity were determined. Adsorption efficiency was found to be affected by factors like pH (2–10), time (5–240 min.), and temperature (288–308 K). It was at pH 6 that the adsorbent reached the point of zero charge. During the adsorption process, electrostatic attraction played an influential role. Adsorption isotherms and kinetics data were well-fitted by Langmuir isotherms and pseudo-second-order models, respectively. A maximum adsorption capacity of 166.60 mg/gm was calculated for 93.90% methyl orange removal and 55.24 mg/gm for 97.30% brilliant green removal. The adsorption process was endothermic, spontaneous, and physical. The rapid desorption of dye molecules confirms the potential, and practicality of the nanocomposite as a promising adsorbent for decolorizing colored wastewater on an industrial scale

Magnetic biochar derived from Juglans regia for the adsorption of Cu2+ and Ni2+: Characterization, modelling, optimization, and cost analysis

Objectives: Indian agricultural wastes such as Juglans regia shells get attention frequently because they can be used as adsorbents. This study aimed to prepare magnetically modified iron oxide immobilized biochar adsorbent using Juglans regia shells and investigate its adsorption capacity for Cu2+ and Ni2+ removal from synthetic wastewater contaminated with metals. Methods: As part of the investigation of the properties of the prepared material and its role in the adsorption process, it was characterized with FTIR, FESEM, EDX, XRD, BET, and VSM techniques. A batch adsorption method was examined by varying pH (2–12), adsorbate concentration (10–100 mg/L), contact time (5–240 min), and temperature (288–308 K). Results: A pH of 6 and an initial concentration of 50 mg/L, as well as equilibrium times of 120 and 150 min, resulted in 98.30 % copper removal and 98.10 % nickel removal, respectively. It was found that both Cu2+ and Ni2+ adsorption was governed by Langmuir's isotherm and obeyed the pseudo-second-order kinetic model. In terms of thermodynamic parameters, it appears that the adsorption of Cu2+ and Ni2+ took place in an endothermic and physical manner. The thermodynamic study determined that the activation energy (KJ/Mol) for Cu was 117.27 and for nickel was 100.24. Using Box-Behnken response surface methodology, the experiments were statistically optimized. Based on the cost estimation study, the prepared adsorbent can be used in metal-contaminated water at a cost-effective rate. Conclusion: Therefore, the prepared magnetic biochar will be useful for the adsorptive removal of Cu2+ and Ni2+ from electroplating wastewater

An Effective Biomass for the Adsorption of Methylene Blue Dye and Treatment of River Water

Neolamarckia cadamba leaves were used as an adsorbent for methylene blue removal as well as for the reduction in the water quality parameters of the sewage belts of Yamuna River in Allahabad, Uttar Pradesh, India. A variety of water quality parameters were assessed, including chemical oxygen demand, biological oxygen demand, total dissolved solids, conductivity, hardness, pH, and temperature. A great deal of degradation in the water quality parameters collected from three locations within the Yamuna River in Allahabad, Uttar Pradesh, India, has been observed by treating with Neolamarckia cadamba leaves. The adsorption studies were carried out by the batch method, and the effect of various parameters such as contact time, pH, initial concentration, and temperature was assessed. The maximum removal of methylene blue was obtained at pH 5 after 120 minutes of equilibrium time. In addition to fitting the Langmuir isotherm most accurately, the adsorbent also followed pseudokinetics of the second order. The maximum monolayer adsorption capacity of used biomass was 101 mg/g using 50 mg/L methylene blue solution. It is evident from the thermodynamic data that the adsorption is exothermic. Also, the spontaneity of the interaction between adsorbent and adsorbate decreases with temperature. Energy-dispersive X-ray spectroscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy techniques were used to characterize the adsorbent. SEM images revealed that the biomass consisted of irregular spherical lumps with a porous structure, which provided effective adsorption sites. A chemical composition analysis of the biomass by EDAX shows that the chemical composition of oxygen and carbon decreases, whereas nitrogen’s chemical composition increases

Novel Hydrolytic Degradable Crosslinked Interpenetrating Polymeric Networks (IPNs): An Efficient Hybrid System to Manage the Controlled Release and Degradation of Misoprostol

Purpose: The goal of this study was to make pH-sensitive HPMC/Neocel C19-based interpenetrating polymeric networks (IPNs) that could be used to treat different diseases. An assembled novel carrier system was demonstrated in this study to achieve multiple functions such as drug protection and self-regulated release. Methods: Misoprostol (MPT) was incorporated as a model drug in hydroxyl-propyl-methylcellulose (HPMC)- and Neocel C19-based IPNs for controlled release. HPMC- and Neocel C19-based IPNs were fabricated through an aqueous polymerization method by utilizing the polymers HPMC and Neocel C19, the initiator ammonium peroxodisulfate (APS), the crosslinker methylenebisacrylamide (MBA), and the monomer methacrylic acid (MAA). An IPN based on these materials was created using an aqueous polymerization technique. Samples of IPN were analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), thermal analysis (TGA), and powder X-ray diffraction (PXRD). The effects of the pH levels 1.2 and 7.4 on these polymeric networks were also studied in vitro and through swelling experiments. We also performed in vivo studies on rabbits using commercial tablets and hydrogels. Results: The thermal stability measured using TGA and DSC for the revised formulation was higher than that of the individual components. Crystallinity was low and amorphousness was high in the polymeric networks, as revealed using powder X-ray diffraction (PXRD). The results from the SEM analysis demonstrated that the surface of the polymeric networks is uneven and porous. Better swelling and in vitro results were achieved at a high pH (7.4), which endorses the pH-responsive characteristics of IPN. Drug release was also increased in 7.4 pH (80% in hours). The pharmacokinetic properties of the drugs showed improvement in our work with hydrogel. The tablet MRT was 13.17 h, which was decreased in the hydrogels, and its AUC was increased from 314.41 ng h/mL to 400.50 ng h/mL in hydrogels. The blood compatibility of the IPN hydrogel was measured using different weights (100 mg, 200 mg, 400 mg, and 600 mg; 5.34%, 12.51%, 20.23%, and 29.37%, respectively). Conclusions: As a result, IPN composed of HPMC and Neocel C19 was successfully synthesized, and it is now possible to use it for the controlled release of MPT

A review of photocatalytic characterization, and environmental cleaning, of metal oxide nanostructured materials

Industrial waste is the primary source of highly toxic organic pollutants and heavy metal contaminants. Treatment of such effluence is necessary to mitigate environmental pollution to provide a clean ecosystem for living species. Various approaches have been effectively utilized for the removal of industrial waste particularly, photocatalysis being an effective, economical, and time-efficient approach to remove toxic ions. Large organic molecules found in pesticides and dyes can be removed with relative ease using nano-photocatalysts with a wide energy band gap, which is one of its major merits. For this purpose, a combination of various metal oxides with relevant materials is generally employed to activate visible regions in photocatalysts. Moreover, modification in physical parameters such as surface area of the catalyst, crystallinity, particle size and morphology, band gap, and microstructure is undertaken, which serves to enhance the photocatalytic activity. Here, advanced techniques that are presently used to synthesize different types of photocatalysts and their potential use in the degradation of the organic dye have been described in detail. The focus of the current review is various metal oxide NPs such as ZnO, TiO2, WO3, SnO2, and CuO with potential applications in photocatalysis, their structural characteristics, classification, and their photocatalytic mechanism. The review covers the influence of dopants on morphological, electrical, optical, and photocatalytic activity of selected nanocomposite systems. Moreover, the current review grasps extensive literature on the role of metal oxides as a photocatalyst that will facilitate researchers by providing guidelines to design more suitable nano-photocatalytic systems

Thigh-length compression stockings and DVT after stroke

Controversy exists as to whether neoadjuvant chemotherapy improves survival in patients with invasive bladder cancer, despite randomised controlled trials of more than 3000 patients. We undertook a systematic review and meta-analysis to assess the effect of such treatment on survival in patients with this disease