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Arsenic is a highly toxic element, and excessive levels can affect human health. Composites possess a larger specific surface area and better adsorption performance than single-MOF materials. In this paper, a simple novel nanocomposite (MnFe₂O₄@Fe-UiO-67) was synthesized by the one-pot method for the removal of arsenic from industrial wastewater. The synthesis and adsorption mechanism of the adsorbent were analyzed by a series of characterizations. The results showed that the adsorption behavior of MnFe₂O₄@Fe-UiO-67 was consistent with the pseudo-secondary kinetics and Langmuir isotherm model, i.e., it is a monomolecular layer chemisorption. Characterization by Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) showed that the active site formed a strong coordination bond (As-O bond) with As ions to achieve efficient adsorption. At 298 K and pH = 10, the arsenic removal rate can reach 98.43%, and the adsorption capacity is 600.25 mg/g, which is more than most of the existing reported adsorbents. Through thermodynamic analysis, it is found that the adsorption of As ions by the adsorbent is a spontaneous exothermic process. It can exhibit excellent adsorption performance at room temperature without the need for additional energy consumption. This adsorbent has great development prospects in the treatment of wastewater. Full article

Many contaminants such as heavy metals, dyes and hydrocarbon compounds are annually generated by industrial activities and discharged into water sources. They have destructive impacts on the environment. To eliminate these toxic contaminants from aqueous media, sorption can be considered a proper and efficient process, as it has indicated high efficiency for removing organic contaminants. This paper entails a comprehensive evaluation of different organic pollutants, pros and cons of the sorption process in removing these pollutants, comparing different types of adsorbents and investigating the recyclability of different types of composites. Moreover, the sorption mechanism and kinetic behavior of organic contaminants are investigated using biocomposites and nanocomposites. Moreover, the future perspectives of biocomposites and nanocomposites in eliminating organic compounds are discussed. Based on investigations, a large number of nanocomposites have been utilized for removing organic contaminants with high performance so far, including SiO₂/MnFe₂O₄/ZIF-8 MOF, magnetite/MWCNTs, nano zerovalent iron, barium/Cobalt/polyethylene glycol (PEG), graphene oxide/Fe₃O₄, kaolin/CuFe₂O₄ and Fe₃O₄@UiO-66. Moreover, polyaniline/sodium alginate/Oscillatoria filamentous cyanobacterium biomass, cow bones/zeolite/coconut biocomposite and AC derived from melamine and sucrose are excellent biocomposites in the removal of organic pollutants. Moreover, the reusability study shows that poly(N-isopropylacrylamide)/Fe₃O₄ and corn stalk biomass/chitosan/Fe₃O₄ biocomposites have significant stability compared to other composites in the elimination of organic pollutants. Full article