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Adsorption has been a widely economical way of removing major pollutants from wastewater in latest times. Zn2+ is a severe human and animal life hazard. The adsorption properties of the chitosan-kaolinite (Ch-K) composite prepared by chemical precipitation for Zn2+ uptake from synthetic polluted water were investigated. The Ch-K composite was analyzed by FT-IR, XRD, SEM and TGA. Under the optimum experimental conditions, the minimum beds average diameter of Ch-K composite was 110 µm. A lot of experiments were done to optimize the adsorption parameters such as concentration of adsorbate, dose of adsorbent, pH and time of contact. The results showed that the Zn2+ sorption onto Ch-K composite were mainly dependent on pH and was affected by the temperature. To express the mechanism of adsorption process and the effect of other parameters on the adsorption time, the kinetic and isothermal models were studied. The second-order kinetics and Freundlich model are suitable for the process. Thus, Ch-K composite has been proved as a potential adsorbent for the removal of Zn2+. [ABSTRACT FROM AUTHOR]

Electrospinning is a promising technique for the beneficial use and recycling of plastic waste polymers using simple methodologies. In this study, plastic bottles and Styrofoam wastes have been used to develop polyethylene terephthalate (PET) and polystyrene (PS) nanofibers using electrospinning technique separately without any further purification. The effect of the concentration onto the nanofiber's morphology was studied. The fabricated nanofibers were characterized using Field Emission Scanning Electron Microscope (FE-SEM), Fourier Transformed Infrared Spectroscopy (ATR-FTIR), N 2 adsorption/desorption analysis, and water contact angle (WCA). Furthermore, the prepared nanofibers were applied for the adsorption of ibuprofen (IBU) from wastewater. Some parameters that can influence the adsorption efficiency of nanofibers such as solution pH, wt.% of prepared nanofibers, drug initial concentration, and contact time were studied and optimized. The results show that the equilibrium adsorption capacity was achieved after only 10 min for 12 wt% PET nanofibers which is equivalent to 364.83 mg/g. For 12 wt% PS nanofibers, an equilibrium adsorption capacity of 328.42 mg/g was achieved in 30 min. The experimental data was fitted to five isotherm and four kinetics models to understand the complicated interaction between the nanofibers and the drug. Langmuir-Freundlich isotherm model showed the best fit for experimental data for both PET and PS nanofibers. The adsorption process was characterized by predominantly physical reaction rather than chemical adsorption for both materials. The reusability study revealed that the synthesized nanofibers maintain their ability to adsorb/desorb IBU for up to five cycles. The results obtained demonstrated that fabricated nanofibers from plastic wastes could perform promising adsorbents for the management of IBU in wastewater. However, further research is needed for the scaling-up the fabrication which is required for real-world applications. [Display omitted] • Plastic Wastes converted into nanofibers for management of ibuprofen in wastewater. • Rapid adsorption kinetics highlights a promising and sustainable direction for pharmaceutical residue removal. • Sustainable and reusable nature of the "as prepared" nanofibers. [ABSTRACT FROM AUTHOR]

In the current study, iron-based metal organic framework (MOF) MIL-101(Fe) was successfully prepared via a facile solvothermal method. The as–synthesized MIL-101(Fe) was characterized by XRD, FE-SEM, FTIR, TGA and zeta potential techniques, and then employed as an adsorbent for methyl orange (MO) and methylene blue (MB) dyes. The adsorbed quantities of MO (1067 to 831 mg/g) were higher than those of MB (402 to 353 mg/g) indicating the high selectivity of MIL-101(Fe) towards the anionic dye at all temperatures (20–60 °C). Adsorption processes of MO and MB followed the pseudo-second order kinetics and the Langmuir equilibrium model. The interaction mechanism at a molecular level was analyzed and deeply interpreted via the advanced multilayer adsorption model. Steric parameters indicated that MO molecular aggregation (n) was 0.95–1.33 thus signifying the presence of multi–docking and multi–interactions mechanisms. The aggregated number of MB was superior to unity (i.e., n = 1.17–1.78) suggesting a vertical adsorption position and a multi-interactions mechanism at all operating temperatures. The density of MIL-101(Fe) active sites (D M = 77.33–52.38 mg/g for MB and 149.91–107.07 for MO) and the total adsorbed dye layers (N t = 3.12–2.49 for MB and 5.36–3.67 for MO) resulted in improving the adsorption capacities of MO dye. The adsorption energies ranged from 8.89 to 33.73 kJ/mol and they displayed that MO and MB uptake processes were exothermic controlled by physical interactions at all temperatures. Regeneration results indicated that this adsorbent can be reutilized without a significant loss in its removal efficiency after five adsorption-desorption cycles. Overall, the adsorption capacity, chemical stability, and regeneration performance of MIL-101(Fe) support its application as a very promising adsorbent for the removal of organic hazardous pollutants from water. • MIL-101 (Fe) MOF was synthesized and used to remove methylene blue and methyl orange from solutions. • Adsorbtion capacities of MO were higher than those of MB in single and binary ystems. • The Langmuir and the advanced multilayer models displayed the best fit for MO and MB adsorption data. • Removal of MO and MB was exothermic and caused by physical interactions. [ABSTRACT FROM AUTHOR]

The efficient elimination of phenolic compounds from the fuel is an important issue because it's adversely affecting the environment and fuel storage stability. Phenol can be removed by various methods including adsorption. Recently, metal organic frameworks (MOFs), both pristine and modified ones, have attracted continuous attention as an adsorbent for the purification of fuel. This paper highlights the synthesis of copper benzene-1,3,5-tricarboxylate (Cu-BTC) supported on kaolin (K) to form Cu-BTC@K composites and examines their adsorption ability of phenol from model oil. The synthesized materials were characterized using XRD, FT-IR, SEM and BET techniques. Although the porosity of the 60% Cu-BTC@K composite was reduced after clay impregnation, the phenol adsorption increased. Investigation results displayed that the phenol adsorption performance by 60% Cu-BTC@K composite was improved up to 817 mg g−1 while with the pure Cu-BTC (676 mg g−1). The 60% Cu-BTC@K composite could be perfectly regenerated for at least 4 cycles with little loss in the adsorption ability. Monte Carlo (MC) simulation was applied to analyze the preferential adsorption sites, the adsorption energies and maximum adsorption capacities. The composites formed by the combination of clay and MOFs may find promising applications in fuel purification. [Display omitted] • Cu-BTC@K was synthesized via the coordination-assisted self-assembly method. • Remarakable removal of phenol by prepared Cu-BTC@ kaolinite was showed 817 mg g−1. • Free site of Cu atoms are the major interaction sites for phenol. • Removal mechanism may be due to H- bonding and and metal- π interaction. [ABSTRACT FROM AUTHOR]