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MIL-101(Cr) stands as one of the extensively researched chromium-based metal-organic frameworks, comprised of chromium metal ions and terephthalic acid ligands. This study introduces an innovative approach to MIL-101(Cr) synthesis by employing ultrasound (UTS) irradiation. Our primary objective revolved around optimizing key operational parameters, namely time and temperature, using the central composite design method. Subsequently, we conducted an in-depth analysis using variance analysis to understand their respective impacts. To predict process behaviour, we developed quadratic equations under varying conditions, achieving a remarkable R2 value of 0.9998 to relate parameters and synthesis yield. Results revealed a more pronounced influence of time variation compared to temperature on the synthesis process. Moreover, we subjected the synthesized MIL-101(Cr) to rigorous characterization using FT-IR, XRD, SEM, TGA, and N2 physisorption techniques. Our findings showcased the synthesized MIL-101(Cr) possessing exceptional characteristics, including an ultra-high specific surface area (2143 m2. g-1), substantial pore size (0.8 cm3.g-1), and excellent thermal, chemical, and water stability. Further examination indicated the presence of microporous windows, mesoporous cages, and uniform octahedral particles ranging in size between 125-260 nm. Notably, our study emphasized the energy efficiency of UTS irradiation over conventional electric (CE) heating, highlighting its potential as a quicker, more efficient, and environmentally friendly alternative to conventional synthesis methods. [ABSTRACT FROM AUTHOR]

Background and Objective: Phenol compounds are commonly applied as raw materials in the production of pesticides, herbicides, and dyes. These compounds are toxic to animals, plants, and microorganisms. In this study, the sonophotocatalytic degradation of 2,4-dinitrophenol in aqueous solutions was investigated using organic-mineral polymer catalysts containing Zink and Cobalt oxides under visible light and ultrasonic (US) irradiation. Materials and Methods: The characteristics of the synthesized catalyst were determined using XRD, FTIR, and SEM techniques. The effect of several key parameters, including pH (3-9), catalyst dosage (0.3-1 g/L), time (0-90 min), US power (100-200 W/m² ), and initial concentration of 2,4-dinitrophenol (20-100 mg/L), on the degradation efficiency was also investigated. Results: After 75 minutes of sonophotocatalytic processing, complete degradation of 2,4-dinitrophenol (20mg/L) was achieved with catalyst dosage of 0.5 g/L, pH of 9.0, and US intensity of 200 W/m² . Kinetic studies indicated that the sonophotocatalytic degradation process followed a first-order kinetic model. The results of radical scavenging experiments confirmed that HO° and O2 ˚- radicals are the main oxidative species involved in the degradation of 2,4-dinitrophenol. Furthermore, the reuse of the catalyst for five consecutive tests showed a slight decrease in removal efficiency. Conclusion: The results demonstrate that the sonophotocatalytic process, using the modified organic-mineral polymers with mixed Zink and Cobalt oxides catalyst, can be an effective method for removing 2,4-dinitrophenol from aqueous media. [ABSTRACT FROM AUTHOR]

Background and Objective: Antibiotics as emerging pollutants are harmful to environmental health. Therefore, this study was conducted to investigate the efficiency of Uio-66-NH2 @CS-Iso-Gu nanohybrid for the removal of amoxicillin (AMX) from aqueous solutions. Materials and Methods: In this study, for the first time, guanidine and isocyanate monomers are cross-linked with chitosan. The combination of this polymer with organometallic compounds contributes to its chemical/thermal stability and reusability. Uio-66-NH2 @CS-Iso-Gu nanohybrid was characterized using X-ray diffraction (XRD), Scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and BET methods. Also, the effects of pH, initial concentration of AMX, contact time, and temperature were evaluated. Moreover, isotherm, kinetic and thermodynamics studies were performed. Results: The results of TGA analysis showed that Uio-66-NH2 @CS-Iso-Gu nanohybrid was resistant to temperatures up to 400 °C. Also, optimal adsorption of AMX occurred in the first 25 min. The synthesized nanohybrid has a surface area of 101.2 m2 /g and a type IV isotherm. Acidic groups were present on the synthesized nanohybrid surface based on the pHpzc = 4.7. Langmuir (for 25 °C and 45 °C) and Freundlich (for 65 °C) isotherm models and pseudo-second-order kinetic models are more appropriate to fit the adsorption data with the experimental data. The maximum adsorption capacity of the synthesized nanohybrid was equal to 56.49, 40.65, and 0.382 mg/g at temperatures of 25°C, 45°C, and 65°C, respectively. Based on the findings, Uio-66-NH2 @CS-Iso-Gu nanohybrid could be used for up to five cycles without significantly reducing their performance. Conclusion: The results showed that Uio-66-NH2 @CS-Iso-Gu nanohybrid has a significant efficiency for removing AMX and could be used as an effective adsorbent for the treatment of wastewater containing pharmaceutical residues. [ABSTRACT FROM AUTHOR]

The synthesis of MIL-53(Fe) samples and encapsulation process of phosphomolybdic acid implemented using ultrasound at ambient temperature and atmospheric pressure. Characterization of newly synthesized nanocomposite was carried out using various techniques such as XRD, FT-IR, SEM, EDS, BET and ICP. The catalytic activity of the prepared nanocomposites, PMA@MIL-53(Fe), was tested through the esterification reaction of oleic acid with ethanol under ultrasonic irradiation. Biodiesel production process using certain molar ratio of oleic acid/ethanol, PMA@MIL-53(Fe) as catalyst (10-200 mg) containing different amounts of PMA (0-40%), at different reaction times (5-20 minutes), total energy consumption (in watts, W) and ambient temperature under ultrasound conditions. The operating conditions of each of parameters were varied to study their effects on product yield. The results indicated that the synthesized composites show excellent catalytic activity. by encapsulating heteropoly acids in the MOF network, the challenges of using heteropoly acids, such as low contact surface and high solubility, are largely eliminated. The use of heteropoly acids in the industrial scales shows promise, provided the mentioned problems can be overcome

Plenty of methods have been introduced to treat the consumed water where the advantages and disadvantages of each method define their applications. Advanced oxidation processes have become a scientific trend due to high removal efficiency. As one of the AOP methods, heterogeneous Fenton method has received plenty of interest because of its high operational capability. In this study, cellulose/CuBDC/Fe3O4 nanocomposite was utilized as heterogeneous Fenton catalyst to remove Direct Blue 71 toxic dye from aqueous media. The catalyst was synthesized as granulated beads to eliminate the operational limitations of utilizing powdered catalysts. The catalysts were characterized by SEM, EDX, FTIR and XRD analysis to validate the successful synthesis procedure. The effects of each component of the nanocomposite on the removal efficiency were investigated. The effective operation of independent parameters such as the initial dye concentration, H2O2 concentration and catalyst dosage were modeled and optimized by RSM design of experiments method. At the optimum point, the removal efficiency of 86.93% was achieved. In addition, the COD of the wastewater was decreased by 73.52%, which demonstrated the high potential of granulated cellulose/CuBDC/Fe3O4 nanocomposite in decomposing organic matter to H2O, CO2, NO2 and SO2. The prepared granulated catalysts retain their removal characteristics over 8-cycle operation.

Objectives: Levothyroxine drug is used to treat thyroid diseases, which is one of the most common chronic diseases in the world, and considering that levothyroxine is a hydrophobic drug with low solubility and low stability, it requires an advanced drug delivery system. Among the targeted drug delivery systems, magnetically modified porous carriers have a high capacity to store drugs due to the presence of side groups, the adaptability of its porosity, and release it over a long period of time and instead of spreading throughout the body, it affects only the desired cell. he does. Materials and methods: The present research deals with preparing and identifying the metal-organic framework and investigating its performance in levothyroxine drug loading and release. First, MnCuFe2O4 nanoparticles were synthesized and covered by alginate polysaccharide. After that, the metal-organic framework 66-UiO was placed on it and the three-layer composite MnCuFe2O4@Alginate@UiO-66 was made. Findings: loading and release of levothyroxine drug on the synthesized nanocarrier was investigated at pH 7.4. The fabricated nanocomposite was examined by various methods such as SEM, EDX, FT-IR, BET. Nanocomposite was made with cheap and biodegradable raw materials such as alginate using an easy method with targeted drug delivery and magnetic strength. Conclusions: This nanocomposite with 87% loading capacity and 73% levothyroxine release can be used as a new and targeted drug delivery system.

Introduction: Toluene is considered as a group of chemical contaminants, causing problems for people’s health. Due to the high rate of evaporation and rapid emission in the surrounding environment, it leads to the exposure of many employees and people at risk and, subsequently, its irreparable effects on their health in different jobs. Therefore, its removal is very important. In the present study, this contaminant was removed using the copper metal-organic framework (MOF) under different operating conditions. Material and Methods: In this study, the copper MOF was synthesized using the one-pot and in situ method. Physical and morphological properties of the adsorbent were investigated using BET, XRD, FTIR and SEM techniques. The efficiency of the adsorbent in removing toluene from the air stream under the dynamic adsorption system was investigated by examining the effect of the variables of adsorbent mass, pollutant concentration and humidity. Isotherm, thermodynamics and kinetics equations were used to evaluate the data. Results: The results of experiments determining the properties of the metal-organic framework showed the formation of pure Cu-BDC crystals with mean and particle size distribution of 1.95 nm. The specific surface area calculated by the BET method for the mentioned sample was 686 m2 g-1 and the total volume of structural pores was 0.335 g3 cm3. The presence of micropores increased the dynamic adsorption capacity of toluene. The findings follow the Langmuir isotherm model and the Pseudo-second order kinetic model. Based on the results of thermodynamic studies, entropy change (ΔS°) and enthalpy change (ΔH°) were equal to -0.44 kJ mol-1 K-1 and -15.67 kJ mol-1, respectively. Gibbs free energy change (ΔG°) was also calculated negatively, indicating that the adsorption process was spontaneous and exothermic. The regeneration of the adsorbent was 77% after three cycles. Conclusion: According to the results of this study, the microporous copper MOF can be used as a result of cheapness, high access, high adsorption capacity and appropriate regeneration rate in different operating conditions for adsorption of toluene.

Photocatalytic removal of bisphenol A, one of the most widely and emerging pollutants in the aquatic environment, was investigated by advanced oxidation process under natural sunlight. The removal process by a metal-organic framework, synthesized with phosphonic acid ligand, namely STA-12 (Fe) and hydrogen peroxide revealed excellent results. Therefore, the optimal conditions for the degradation of bisphenol A by the photo-Fenton mechanism were studied. The removal process follows the first-order kinetics with respect to the contaminant and a significant synergy was observed in the catalytic system of hydrogen peroxide/sunlight/STA-12 (Fe). The Optimal values for pH, irradiation time, catalyst amount and H2O2 dosage for oxidation of bisphenol A in 30 mg / l aqueous solution were determined to be 5, 90 minutes, 10 mg and 12 μl, respectively. Under these conditions, the best removal efficiency was 79.8%. Also, the mineralization value of organic pollutant was determined to equal 51% by measuring TOC. To determine the most important species that affected the photocatalytic reduction, trapping experiments were carried out, using various kinds of scavengers and the results showed that the hydroxyl radicals (•OH) are the main oxidizing agent in the photocatalytic system and superoxide radical and the holes in the photocatalyst surface are less involved in the process of contaminant degradation. Finally, a probable reaction mechanism has been investigated in detail. In addition, the catalyst has recyclability and stability in the photocatalytic reaction. This study is the first report for application of a phosphonate-based MOF for the removal of an emerging pollutant with a photo-Fenton mechanism and presents a new example of solar-driven advanced oxidation process for the treatment of aquatic sources and environmental protection.

In this research, the effect of hydrogen peroxide (H2O2) and benzoyl peroxide (BPO) on the structural properties, porosity, active pores, and surface area of the MOF-5 (Zn4O(BDC)3) metal-organic framework was studied. For this purpose, the metal-organic framework was synthesized by direct mixing and the molar ratios of the precursors to the ligand were modified to minimize the stoichiometric calculation error as well as the washing process to improve the properties of the synthesized MOF-5. In order to characterize the synthesized compounds and to investigate the effect of peroxides and washing process on the properties of the samples, X-ray diffraction (XRD), fourier Transform infrared spectroscopy (FTIR), and thermogravimetric/Differential scanning calorimetry (TG-DSC) analysis were performed. Structure, pore volume (1.212 cm³/g), and specific surface area (2307 m²/g) were compared to the sample synthesized with H2O2. DM-P-03 was selected as the optimal sample and prepared for thermal stability. According to TG-DSC analysis, the remaining zinc compounds in the sample were checked and the thermal stability of MOF-5 structure was confirmed up to 470°C. [ABSTRACT FROM AUTHOR]

Polyaniline/Co(II) metal-organic framework composites (PANI/x%Co-MOF) were synthesized by hydrothermal preparation of Co(II) metal-organic framework in the presence of as-prepared polyaniline. The composites were characterized using powder X-ray diffraction (PXRD), fourier-transform infrared (FT-IR), scanning electron microscopy (SEM), and Co elemental EDS-mapping. Crystal stability of Co(II) metal-organic framework in the composites was confirmed by powder X-ray diffraction. The Co elemental EDS-mapping shows that the cobalt is uniformly dispersed in the polymer matrix. Electrochemical properties of prepared composites were evaluated by cyclic voltammetry (CV) and galvanostatic charge/discharge methods in a conventional three-electrode system. The results of electrochemical studies showed that the PANI/50%Co-MOF composite has the highest specific capacitance, 144 F g-1, at 1 A g-1 current density in KNO3 (3 M) electrolyte. The composite electrodes have shown a higher capacity than pure polyaniline and Co(II) metal-organic framework, due to the synergistic effects.

In this work, with a simple and mild method, 1,5-benzodiazepine compounds were synthesized using the condensation of o-phenylenediamine derivatives and liner and cyclic ketones in the presence of the metal-organic framework Zn3(BTC)2 in ethanol at 50 °C. All products with excellent yields (86-94%) were obtained. Nanoparticles Zn3(BTC)2 have the advantages such as non-toxic, stable in solvents and harsh conditions, easy synthesis, high activity, easy separation from the reaction mixture by filtering and recyclable without losing its activity. In this work, with a simple and mild method, 1,5-benzodiazepine compounds were synthesized using the condensation of o-phenylenediamine derivatives and liner and cyclic ketones in the presence of the metal-organic framework Zn3(BTC)2 in ethanol at 50 °C. All products with excellent yields (86-94%) were obtained. Nanoparticles Zn3(BTC)2 have the advantages such as non-toxic, stable in solvents and harsh conditions, easy synthesis, high activity, easy separation from the reaction mixture by filtering and recyclable without losing its activity.

Development of wastewater treatment methods has become a hot research topic. The advanced oxidation processes (AOPs) have attracted much attention as a method for degrading a wide range of non-biodegradable and harmful organic pollutants into less toxic compounds. In this work, TMU-16 a two-fold interpenetrated mesoporous MOF as a heterogeneous catalyst was employed to photodegradation of Eriochrome Black T under UV irradiation from aqueous solution. Some parameters such as pH, catalyst amount and dye concentration which affect the efficiency of the degradation were studied. From kinetic studies, the degradation producer is the pseudo-first-order. The detection of hydroxyl radicals with probe molecule and perform degradation in the absence of O2 molecules revealed that degradation occurred by mediated these radicals. The results shown, that TMU-16 should be effective photocatalyst for dyes degradation.