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It is imperative to eliminate heavy metals and pharmaceutical residual pollutants from wastewater to reduce their detrimental effects on the environment. In this work, natural zeolite and a 2-amino terephthalic acid-based multi-metallic organic framework were used to create a new composite that can be utilized as an adsorbent for cadmium and safinamide. The adsorption study was examined in a variety of settings (pH, adsorbent dosage, pollutant concentration, and time). Moreover, Zeta potential, BET, SEM, FTIR, XRD, and SEM measurements were used to characterize the adsorbents. The adsorption process was confirmed using FTIR, XRD, and SEM analysis. Various nonlinear adsorption isotherm models were applied to adsorption results. The results showed a significantly better adsorption ability for safinamide and cadmium using zeolite/MOF compared to zeolite. Adsorption kinetics were represented by five models: pseudo first-order, pseudo second-order, intraparticle diffusion, mixed first- and second-order, and the Avrami model. Regarding both adsorbent substances, safinamide adsorption was best represented by the intraparticle diffusion model. In contrast, the pseudo second-order and intraparticle diffusion models for zeolite and zeolite/MOF, respectively, better fit the experimental results in the case of cadmium adsorption. The thermodynamic parameters ΔH°, ΔS°, and ΔG° were investigated through temperature tests carried out at 25, 35, 45, and 55 °C. Exothermic and spontaneous adsorption processes were demonstrated by the computed values. The study of adsorbent regeneration involved the use of several chemical solvents. The DMSO solvent was shown to have the highest adsorbent regeneration method efficiency at 63%. Safinamide elimination was lessened by organic interfering species like cefixime and humic acid compared to inorganic species like chloride, sulphate, and nitrate, most likely as a result of intense competition for the few available active sites. Using zeolite/MOF nanocomposite, the percentage of safinamide removed from spiked real water samples (tap water, Nile River water, and groundwater samples) was 48.80%, 64.30%, and 44.44%, respectively. Based on cytotoxicity results, the highest percentages of cell viability for zeolite and zeolite/MOF at 24 h were 83% and 81%, respectively, in comparison to untreated controls. According to these results, zeolite and zeolite/MOF composites can be used as effective adsorbents for these pollutants in wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • UiO-66-(COOH) 2 MOF and its modification by cupper and iron were synthesized. • Remarakable removal of diclofenac by prepared MOFs was observed. • Zr atoms are the major interaction sites for DCF as they have the higher charge than Cu and Fe. • Remval mechanism may be due to H- bonding and and metal- π interaction. Water pollution by pharmaceuticals is currently a great concern due to their ecological risks. In this study, zirconium-based metal–organic frameworks (UiO-66-(COOH) 2) were used for removal of the nonsteroidal anti-inflammatory drug (NSAID) diclofenac sodium (DCF). They have been synthesized using a hydrothermal method. Copper and iron metal ions were incorporated in the framework using post-synthetic modification techniques to produce UiO-66-(COOCu) 2 and UiO-66-(COOFe) 2. The resulted MOFs were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning/transmission electron microscopy, and Brunauer–Emmett–Teller. The effects of the pH, initial concentration, and adsorption time on the adsorption process of diclofenac were studied. The maximum adsorption capacities obtained on UiO-66-(COOH) 2 , UiO-66-(COOCu) 2 , and UiO-66-(COOFe) 2 were 480.5, 624.3, and 769.1 mg/g, respectively. The adsorption of diclofenac was found to be better fitted with Langmuir isotherm and pseudo-second-order kinetic models. The adsorption mechanism was investigated using XRD, FT-IR, density functional theory and Monte Carlo simulation, in which the latter method was used to calculate the adsorption energies and determine the possible interactions between diclofenac and the adsorbents. UiO-66-(COOH) 2 , UiO-66-(COOCu) 2 , and UiO-66-(COOFe) 2 exhibited good recyclability for diclofenac removal, which confirms the sustainability of these materials. [ABSTRACT FROM AUTHOR]

In this work, the removal of a model antibiotic named 'doxycycline' by three‐layered double hydroxides (LDHs) such as Mg–Fe LDH, Mg–Al LDH and Mg–Al/MWCNT LDH was investigated. Almost full characterisation of the prepared LDHs before and after adsorption was conducted using X‐ray diffraction, Fourier‐transform infrared spectroscopy, zeta potential, Brunauer–Emmett–Teller used for detecting the surface area, high‐resolution transmission electron microscope (HRTEM) and field emission scanning electron microscope. The effect of different factors on doxycycline adsorption capacity was investigated. The removal percentages of doxycycline were 80, 82 and 92% by Mg–Fe LDH, Mg–Al LDH and Mg–Al/MWCNT LDH, respectively. These results were attributed to the difference in the pore volume and geometry between the different LDHs. The isothermal and kinetic models of adsorption were also studied. The kinetics of adsorption were described by the second‐order equation with a better fit showed by a high R2 value. Mathematically, the Langmuir and Freundlich models best fitted the equilibrium data. [ABSTRACT FROM AUTHOR]

• ZnFe-layered double hydroxide (LDH) was synthesized and characterized. • ZnFe-LDH showed efficient adsorption capacity for diclofenac from water. • The adsorption mechanism was investigated. • In- vivo toxicity study in mice showed the safety of Zn–Fe LDH. Layered double hydroxide (LDH) has great application in the treatment of organic pollutants. In this study, Zn–Fe LDH was prepared by co-precipitation method and characterized using different analytical instruments including X-ray diffractometer (XRD), zeta potential, Fourier-transform infrared spectrometry (FTIR) spectroscopy, X-ray diffractometer (XPS), Field emission scanning electron microscope (FESEM), and High resolution transmission electron microscope (HRTEM). Also, the efficiency of Zn–Fe LDH as adsorbent for the removal of diclofenac sodium (DCF) from aqueous solution was investigated under different experimental conditions, such as pH, dose of adsorbent, pollutant concentration, and contact time. The Zn–Fe LDH has successfully removed a high percentage of diclofenac from water within 30 min, and its adsorption capacity at equilibrium was 74.50 mg/g. Several isothermal and kinetic models of the adsorption process were investigated. It was found that diclofenac adsorption was best fitted with three and four-parameter isotherms and the pseudo-second order kinetic model. The surface adsorption mechanism was explored computationally by means of Monte Carlo and molecular dynamic simulations in gas and water phases. The simulation results have shown that diclofenac strongly interacts with Zn–Fe LDH through a variety of hydrogen bonds, as well as metal complexation. The in-vivo toxicity study in mice revealed the safety of Zn–Fe LDH on different body organs through estimation the median lethal dose that kill 50% of the animal numbers. [ABSTRACT FROM AUTHOR]