A series of flexible metal–organic frameworks (MOFs) belonging to the MIL-53 family, such as MIL-53(Al), its amino-functionalized analog NH₂-MIL-53(Al), and MIL-53(Al) type materials with Al³⁺ ions and mixed benzene-1,4-dicarboxylate and 2-aminobenzene-1,4-dicarboxylate linkers (MixLR) in various proportions were prepared in a nanocrystalline form using MW-activation under atmospheric pressure according to the original solvothermal procedure. The MIL-53(Al) and NH₂-MIL-53(Al) samples feature nanocrystals with sizes of 200–300 nm, while MixLR matrices synthesized in this manner are composed of small nanoparticles with sizes of about 20–30 nm. MIL-53(Al) type materials (MIL-53(Al), NH₂-MIL-53(Al) and MixLR) were probed in the adsorption of a typical herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in an aqueous medium. This study revealed a strong impact of the flexibility and porosity of the synthesized MIL-53(Al) type matrices on their physicochemical characteristics. MIL-53(Al) type materials show much higher 2,4-D adsorption rates than an activated carbon matrix (CSAC). The structural characteristics of the studied MIL-53(Al) type materials were established with a high resolution X-ray powder diffractometer equipped with a synchrotron radiation source. The obtained results can be used for the development of advanced adsorbents based on MIL-53(Al) type materials for water remediation.

Recent developments in the use of activated carbons (ACs) of various geneses for wastewater treatment to remove copper, nickel, cadmium, and lead ions, whi

Industrial wastewater is the main source of an excessive amount of molybdenum (Mo) in natural ecosystems. It is necessary to remove Mo from wastewater before it is discharged into the environment. Molybdate ion(VI) is the most common form of Mo in natural reservoirs and industrial wastewater. In this work, the sorption removal of Mo(VI) from an aqueous medium was evaluated using aluminum oxide. The influence of such factors as the pH of the solution and the temperature was evaluated. Three adsorption isotherms, namely, Langmuir, Freundlich and Temkin, were used to describe the experimental results. It was found that the pseudo-first order kinetic model better fits the kinetic data of the adsorption process, and the maximum Mo(VI) adsorption capacity was 31 mg/g at 25 °C and pH 4. The thermodynamic parameters indicated that the process of Mo(VI) adsorption on Al₂O₃ was exothermic and spontaneous. It was shown that the adsorption of Mo strongly depends on pH. The most effective adsorption was observed at pH values below 7. Experiments on adsorbent regeneration showed that Mo(VI) can be effectively desorbed from the aluminum oxide surface into a phosphate solution in a wide range of pH values. After the desorption of Mo(VI) in a phosphate solution, alumina was found to be suitable for repeating the procedure at least five times.

The literature sources containing information and description of experiments on the regeneration of activated carbons containing biologically active organi

The adsorption of 2,4-dichlorophenoxyacetic acid on the samples of activated carbons modified with iron compounds to acquire magnetic properties of these s

The kinetics of adsorption of salicylic acid from aqueous solutions on microporous granular activated carbon (GAC) was studied. The high adsorption capacit