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[Display omitted] Water contamination with antibiotics promotes environmental antibiotic resistance. Tetracycline(TC), commonly used in agriculture, pollutes water and enables bacteria to develop resistance genes. Mg-Al-layered double hydroxides/Activated carbon (Mg-Al-LDH/AC) nanocomposite effectively removes tetracycline from water in this study. The synthesized adsorbent was characterized using Brunauer–Emmett–Teller (BET), Fourier-transform Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDS) tests, and exhibited a large surface area of 105.46 m2/g, a total pore volume of 0.4571 cm3/g, and an average pore diameter of 27.99 nm. The optimal conditions for eliminating TC using the Mg-Al-LDH/AC nanocomposite were determined via the central composite design response surface methodology (CCD-RSM) approach. The responses were evaluated using a second-order polynomial multiple regression model, which was found to be a satisfactory fit to the data based on the analysis of variance (R2 = 0.9690, R2 Adj = 0.9478, and R2 Pred = 0.9042). The ideal conditions were identified as pH = 5.1, 0.11 g of adsorbent, a TC concentration of 50 mg/L, and a contact time of 90 min. The adsorption isotherms showed that TC elimination follows the Langmuir model with a maximum adsorption capacity of 106.4 mg/g and a high R2 value of 0.9986. The kinetics of the TC adsorption process was found to fit the pseudo-second-order model with a correlation value of 0.9997. The values of ΔG, ΔH, and ΔS for TC were determined to be 1.90 kJ/mol (at 333.15 K), −41.97 kJ/mol, and −0.131 kJ/(mol·K), respectively. Additionally, the study showed that ionic strength did not affect the effectiveness of TC removal, and the adsorbent was effective in removing TC antibiotics in a range of ionic strengths. Finally, the study found that adding 20% by weight of AC to LDH resulted in the best TC removal efficiency. [ABSTRACT FROM AUTHOR]

Zinc oxide/poly(vinyl alcohol) nanocomposite (ZnO/PVA) has unique structural and functional properties, leading to excellent potential in many electrical, optical, water treatment, and medical fields. According to the broad applications of this composite in different sciences, a comprehensive study of its various aspects is necessary. Based on our knowledge, no complete research has yet been carried out to address all its aspects. Then, in five major parts, this review study, then, investigated various aspects of the ZnO/PVA nanocomposite. In the "Introduction" section, ZnO nanoparticles, PVA polymer, and ZnO/PVA composite were illuminated. In this section, the ZnO/PVA composite was compared with some nanocomposites. The "properties" section examined the properties of the composite, such as optical, electrical, thermal, mechanical, and morphological properties. In the "synthesis" section, the synthesis methods of this composite and their instructions were discussed. The synergistic effect of ZnO and PVA on each other was thoroughly investigated in the same section. The "applications" section then detailed the applied aspects of ZnO/PVA composite, ranging from water treatment to the medical field. Many research efforts have been made to address the inherent shortcomings of this nanocomposite. In the "modification" section, an overview was done on several materials (including metal, metal oxide, carbon, and natural and synthetic polymers), used to design an appropriate and logical ZnO/PVA modification to form a better structure. It is expected that this overview would offer useful information for researchers in different fields, such as measurement, electromagnetic protection, water treatment, energy storage, and medical science. • Comprehensive review of the ZnO/PVA composite, including characteristics, synthesis methods, and applications is provided. • The synergistic combination of ZnO nanoparticles and PVA, improves the various properties of this composite. • The mechanical, electrical, and thermal capabilities of ZnO/PVA composite can be enhanced by adding some other modifiers. • Some constructive suggestions for further applications of modified ZnO/PVA composite are proposed. [ABSTRACT FROM AUTHOR]

In this study, the removal of malachite green (MG) with Ca-Al-LDH-S 2 O 3 as an adsorbent was studied. Treatment of LDH with thiosulfate ions caused to improvement the interlayer distance of adsorbent. [Display omitted] Malachite green from the tri-aryl methane cationic dyes family, despite being toxic, is widely used in many industries. In this study, the removal of malachite green (MG) with Ca-Al-LDH-S 2 O 3 as an adsorbent was studied. Treatment of LDH with thiosulfate ions caused improvement in the interlayer distance of the adsorbent. This adsorbent was synthesized by the co-precipitation method and used to remove malachite green in an aqueous solution. Adsorbent properties were studied using SEM, XRD, BET, FTIR, and DSC techniques. BET surface area for adsorbent was 205.15 m2 g−1. The experimental parameters containing pH = 7.0, adsorbent dose = 0.1 g, initial concentration of pollutant = 100 mg mL−1 and contact time = 120 min were obtained as optimal conditions. Investigation of isotherm models showed that the Freundlich model better fits with the experimental data than the Langmuir model. The maximum capacity at saturation conditions was 909.09 mg g−1. The Pseudo-Second-Order kinetic model was obtained as a dominant kinetic model. The obtained thermodynamic parameters showed that the adsorption process is spontaneous, endothermic and was associated with an increase in system irregularity. [ABSTRACT FROM AUTHOR]