shima Amani; Mohammad Rostamizadeh; Ali Ghadimi
Abstract
In this study, zeolitic imidazolate framework (ZIF-8) nanocatalyst was synthesized by the thermal solvent method and doped by Fe species through wet impregnation technique. The nanocatalysts were applied for the degradation of Phenazopyridine Hydrochloride (PHP) through the heterogeneous Electro-Fenton ...
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In this study, zeolitic imidazolate framework (ZIF-8) nanocatalyst was synthesized by the thermal solvent method and doped by Fe species through wet impregnation technique. The nanocatalysts were applied for the degradation of Phenazopyridine Hydrochloride (PHP) through the heterogeneous Electro-Fenton (HEF) process. The nanocatalysts were characterized by XRD, BET-BJH, FT-IR, FE-SEM, TEM, and acidimetric-alkalimetric titration techniques. The results showed the high surface area (1335 m2g-1) and homogenous dispersion of Fe species. The influence of different operating conditions was investigated, including pH level, nanocatalyst concentration, applied current, and PHP concentration. The optimum conditions for the HEF system over the Fe-ZIF-8 nanocatalyst were pH=7, 0.2 g L-1 of the Fe-ZIF-8 nanocatalyst, 100 mA, and 10 ppm of PHP concentration, which resulted in 99% PHP removal. The developed nanocatalyst had high reusability for the PHP removal in the HEF process. The results confirm the high potential of ZIF-8 nanocatalyst for pharmaceutical wastewater treatment through the HEF process.
Mohammad Reza Mohammad Shafiee; Janan Parhizkar; Sasan Radfar
Abstract
Homogenous catalysis which the catalyst operates in the same phase as the reactants is definitely efficient in catalysis processes while it suffers from the impossibility or inconvenience of the removal of the catalyst from the reaction media. In this research, In2S3 nanoparticles were synthesized by ...
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Homogenous catalysis which the catalyst operates in the same phase as the reactants is definitely efficient in catalysis processes while it suffers from the impossibility or inconvenience of the removal of the catalyst from the reaction media. In this research, In2S3 nanoparticles were synthesized by a simple precipitation method and then immobilized and stabilized in the porous structure as a substrate. The properties of pure hydrogel and In2S3 in hydrogel were characterized by FTIR, DRS, XRD, BET, BJH, FESEM, and EDX. The DRS results confirmed that the stabilization of nanoparticles in hydrogel led to redshift of bandgap. The hydrogel with In2S3 showed a more porous structure in comparison with pure hydrogel. Because of the decrease of bandgap and increase of specific surface area, In2S3 nanoparticles stabilized in hydrogel removed Rhodamine B (RhB) as a model pollutant very well. The performance of catalyst in the removal of RhB under dark condition (adsorption) and visible light irradiation (photocatalysis) was investigated and 77.7% and 95.2% of dye removal percentage were obtained in 120 min under dark and light irradiation, respectively. In conclusion, immobilization In2S3 as a high-efficiency visible light photocatalyst in hydrogel provided promising heterogeneous and reusable catalyst for water treatment
Bahram Bagheri; Seyed Ali Hosseini; Habib Mehrizadeh
Abstract
The catalytic wet peroxide oxidation of phenol from aqueous wastewater and COD reduction over Cu-Mn2 and Cu-Co2 nano mixed oxides are reported. The effects of process variables of pH, reaction time and hydrogen peroxide dosage were investigated in the process over both catalysts. The catalysts were characterized ...
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The catalytic wet peroxide oxidation of phenol from aqueous wastewater and COD reduction over Cu-Mn2 and Cu-Co2 nano mixed oxides are reported. The effects of process variables of pH, reaction time and hydrogen peroxide dosage were investigated in the process over both catalysts. The catalysts were characterized by X-ray diffraction (XRD) and it was concluded that the mixed oxides are in the form of the spinel structure. However, a little bit CuO was found in the mixed oxides. The morphology and particles size of the catalysts were investigated by scanning electron microscope (SEM). The morphologies and particle size of the catalyst were approximately the same with an average range of 40-60 nm. The catalytic results indicated the higher activity of CuCo2O4 spinel. The phenol oxidation on Cu-Co2 oxide was 82% after 40 min, whereas on the Cu-Mn2 oxide was 78% even after 50 min. The COD reduction The higher activity and reusability of the Cu-Co2 catalyst is attributed to the high synergistic effect between CuO particles and Cu–Co2 spinel, promoting phenol degradation.
Ahmad Vakili Tajareh; Hossein Ganjidoust; Bita Ayati
Abstract
In this study, TiO2/Fe3O4 and TiO2/Fe3O4/MWCNT as a new magnetic nanophotocatalytic materials were synthesized. For this, TiO2 nanoparticle were fixed on an inert surface by sonochemical method. X-ray Diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (DRS), ...
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In this study, TiO2/Fe3O4 and TiO2/Fe3O4/MWCNT as a new magnetic nanophotocatalytic materials were synthesized. For this, TiO2 nanoparticle were fixed on an inert surface by sonochemical method. X-ray Diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (DRS), vibration sample magnetometry (VSM) were used to characterize the magnetic nanocomposites. SEM analysis indicated that TiO2 and Fe3O4 nanoparticles were adhered to MWCNT. Ability of the nanocomposites to remove organic pollutants were investigated by photodegradation of Acid Red 14, Acid Blue 19, Reactive Red 77, and Methyl Orange dyes simulated conditions similar to sunlight. Furthermore, the removal efficiency of AR14 were investigated under direct sunlight irradiation, with an initial concentration of 50 mg/L by TiO2, TiO2/Fe3O4 and TiO2/Fe3O4/MWCNT nanocatalysts were 89.83, 21.19 and 86.27, respectively. According to the results, addition of carbon nanotubes to the TiO2/Fe3O4 magnetic nanocomposite, increased the efficiency of AR14 photodegradtion through change in energy gap visible waves and the scavenging role of carbon nanotubes. Also, The reusability of nanocomposites was assessed in five consecutive cycles of 6 hours, The results showed that after 5 cycles the degradation rate decreased only 7.79 %.
Ouahiba Bechiri; Mostefa Abbessi
Abstract
The main objective of this work is to study the oxidation of naphthol blue black (NBB) in aqueous solution by hydrogen peroxide using a recyclable Dawson type heteropolyanion [H1.5Fe1.5P2W12Mo6O61.23H2O] as catalyst.The effects of various experimental parameters of the oxidation reaction of the dye were ...
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The main objective of this work is to study the oxidation of naphthol blue black (NBB) in aqueous solution by hydrogen peroxide using a recyclable Dawson type heteropolyanion [H1.5Fe1.5P2W12Mo6O61.23H2O] as catalyst.The effects of various experimental parameters of the oxidation reaction of the dye were investigated. The mineralization of the dye was investigated by the total organic carbon (TOC) measurement in optimum conditions. The influence of the catalyst nature (Dawson- type iron -substituted heteropolyanion) and (Dawson- type copper -substituted heteropolyanion) on the oxidation process was investigated. The catalytic oxidation using a recyclable heteropolyanions as catalysts is an economically and environmentally friendly process to remove the toxicity of the recalcitrant compounds in water.
Tooraj Beyki; Mohammad Javad Asadollahzadeh
Abstract
For the first time, uniform molecularly imprinted polymer (MIP) nanoparticles were prepared using dicamba as a template. The MIP nanoparticles were successfully synthesized by precipitation polymerization using methacrylic acid (MAA) as functional monomer, trimethylolpropane trimethacrylate (TRIM) as ...
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For the first time, uniform molecularly imprinted polymer (MIP) nanoparticles were prepared using dicamba as a template. The MIP nanoparticles were successfully synthesized by precipitation polymerization using methacrylic acid (MAA) as functional monomer, trimethylolpropane trimethacrylate (TRIM) as cross-linker and acetonitrile as porogen. The produced polymers were characterized by differential scanning calorimetry (DSC) and their morphology was precisely examined by scanning electron microscopy (SEM). The MIP nanospheres were obtained with the average diameter of 234 nm. Batch-wise guest binding experiments were carried out to determine the removal efficiency of the produced MIP nanoparticles towards the template molecule in aqueous solutions. The MIP showed outstanding affinity toward dicamba in aqueous solution with maximum removal efficiency of 87.5% at 300 mg.L-1 of dicamba solution. The MIP exhibited higher adsorption efficiency compared with the corresponding non-imprinted polymer (NIP) as well as outstanding selectivity towards dicamba relative to the template analog in an aqueous solution. Moreover, effects of pH on removal efficiency and selectivity of MIP were evaluated in detail.