Ahdieh Bavi; Mohammad Ghorbanpour; Mohammed Jaafar Ali Alatabe
Abstract
This study investigated the removal of methylene blue dye from aqueous solutions using Mg solid state exchanged bentonite. Parent bentonite and magnesium exchanged bentonite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET), Energy dispersive ...
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This study investigated the removal of methylene blue dye from aqueous solutions using Mg solid state exchanged bentonite. Parent bentonite and magnesium exchanged bentonite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET), Energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR). The parent bentonite showed the lowest removal efficiency (40.3%) and prepared magnesium exchanged bentonite for 10 min showed the highest removal efficiency (54.8%). Thus, dye absorption by modified bentonite increased compared to parent bentonite. After its modification by the ion exchange method, the specific surface was changed from 44.5 to 56.05 M2/g. EDX results indicate that the cation exchange process has been completed successfully. Ion exchange causes some minor changes in bentonite morphology and crystallinity. The best conditions for removing methylene blue using magnesium exchanged bentonite was pH 10, adsorbent dosage 0.05 mg/liter, initial concentration of solution 100 mg per liter, and contact time of 120 minutes with a Removal efficiency of 96.67. The Langmuir isotherm had a better correlation coefficient than the Freundlich adsorption model, which indicated the homogeneous surface of the adsorbent.
Hassanali Rasouli; Faezeh Jafarpisheh; Mohammad Ghorbanpour
Abstract
Dyes are produced as water pollutants in the textile, plastic, and dye industries. Many efforts have been made to remove dyes from industrial wastewater. In this area, Photocatalytic performance under Vis-lights is a useful and effective method. In this study, a series of highly efficient Sn-doped TiO2 ...
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Dyes are produced as water pollutants in the textile, plastic, and dye industries. Many efforts have been made to remove dyes from industrial wastewater. In this area, Photocatalytic performance under Vis-lights is a useful and effective method. In this study, a series of highly efficient Sn-doped TiO2 photocatalysts were successfully developed using a simple heat treatment process. Three concentrations of SnCl2 powder (3%, 5%, and 7 %) were used for the preparation of materials. The characterizations of resulting materials were distinguished by scanning electron microscopy (SEM), diffusion reflection spectroscopy (DRS), and X-ray diffraction spectroscopy (EDX). Also, methyl orange dye was served to indicate the photocatalytic activity of Sn-doped material under visible light irradiation. The results indicated that both doped and also pure TiO2 have a uniform size. Anatase was the only identified phase in all the products, whether doped or un-doped. The resulting Sn-doped materials have demonstrated a band gap value range of 3.14 to 2.68 eV in comparison with pure TiO2 which shows a value of 3.2 eV. The photocatalytic evaluations indicated that the samples prepared in the presence of 3, 5, and 7% SnCl2 have degradation efficiencies of 85%, 85%, and 90%, respectively within 120 min, which are much higher than that of un-doped TiO2. The enhancement in the efficiency was attributed to the gap changes in anatase by the incorporation of Sn ions into the TiO2 lattice structure. Compared to pure TiO2, which has a band gap of 3.2 eV, the band gap values for doped TiO2 ranged from 3.14 to 2.68 eV.
Mohammad Ghorbanpour; Atabak Feizi
Abstract
The aim of the present study is to synthesize and characterize Fe-doped TiO2 nanoparticles prepared by molten salt method using a precursor of a solid mixture of TiO2 powder and FeCl3. As far as this study is concerned, this is the simplest method that has been reported so far for the synthesis of Fe-doped ...
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The aim of the present study is to synthesize and characterize Fe-doped TiO2 nanoparticles prepared by molten salt method using a precursor of a solid mixture of TiO2 powder and FeCl3. As far as this study is concerned, this is the simplest method that has been reported so far for the synthesis of Fe-doped TiO2 nanoparticles. Pure TiO2 nanoparticles and 0.5, 1 and 3 wt % Fe-doped TiO2 samples were prepared. Characterization of prepared nanoparticles was done by UV-Vis diffusion reflection spectroscopy (DRS), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Energy-dispersive X-ray spectroscopy (EDX). SEM and XRD analysis of the samples indicated the presence of anatase spherical-shaped TiO2 particles. The results of EDX study confirmed the presence of Fe in all of the samples. According to DRS results, the band gap energy of Fe doped TiO2 nanoparticles decreased with increasing Fe concentration from 3.1 eV for pure TiO2 to 3.0- 2.80 eV for Fe-doped TiO2. The photocatalytic activity was also checked. It was found that, the photocatalytic activity of Fe-doped nanoparticles was higher than pure TiO2. The maximum degradation activity of 69% was obtained at the Fe doping content of 0.5 wt%.
Bahareh Hakimi; Mohammad Ghorbanpour; Atabak Feizi
Abstract
ZnO/bentonite photocatalyst was synthesized using different methods, including: precipitation, liquid-state ion exchange (LSIE) and solid-state Ion exchange (SSIE) methods. In most studies done so far, LSIE and precipitation method have been used to prepare composites. The SSIE is a new method. The purpose ...
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ZnO/bentonite photocatalyst was synthesized using different methods, including: precipitation, liquid-state ion exchange (LSIE) and solid-state Ion exchange (SSIE) methods. In most studies done so far, LSIE and precipitation method have been used to prepare composites. The SSIE is a new method. The purpose of this research is to produce nanocomposites with each of these methods and compare their photocatalytic activity. The physicochemical properties of the prepared photocatalysts were determined by scanning electron microscope (SEM), energy dispersive X-ray (EDX) and diffusive reflective spectroscopy (DRS) analysis. The Photocatalytic activity was evaluated by degradation of methyl orange (MO) with the prepared photocatalysts. SEM images showed that the ZnO particles were successfully distributed on the bentonite in the samples prepared by precipitation method. Nevertheless, after ion exchange-based methods, no particles were formed on the bentonite surface. This is because of very small size of ZnO particles which in the interlayer space of bentonite. The EDX and DRS analysis confirmed the formation of composites. The photodegradation of MO were 84, 85 and 87% for the composites prepared by LSIE, SSIE and precipitation methods, respectively. Ultimately, the photocatalytic composites prepared by the solid-state method are very bright due to their simple production, low price and short time due through direct heating of the reaction.
Mohammad Ghorbanpour; Mohsen Moghimi; Samaneh Lotfiman
Abstract
In this research, a simple and fast method was employed to synthesize CuO nanoleaves/silica gel nanocomposites (CuO/SGn), which is a cost effective antimicrobial material. CuSO4.5H2O is the only raw material used in CuO/SGn production through the molten salt method. The structure and morphology of the ...
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In this research, a simple and fast method was employed to synthesize CuO nanoleaves/silica gel nanocomposites (CuO/SGn), which is a cost effective antimicrobial material. CuSO4.5H2O is the only raw material used in CuO/SGn production through the molten salt method. The structure and morphology of the nanocomposites were characterized by DRS, XRD, and SEM. The copper size in CuO/SG was found to be dependent on the immersion time in molten salt. SEM images revealed smaller-sized particle leaves, from a sample obtained after longer immersion time.The antimicrobial activity of CuO/SGn was investigated against Escherichia coli. The produced CuO/SGn showed inhibitory effect against E. coli. However, the growth-inhibitory effect depends on the copper content and size. Lower loading of CuO nanoparticles in 10 min immersion time resulted in less antibacterial activity (73.33%) and sample obtained from longer immersion time demonstrated higher antibacterial activity (up to 99.96%). The maximum amount of released Cu ions from nanocomposites produced in 90 min was 12.2 ppm after 6 h. Furthermore, the minimum release of Cu ions was observed by 3 h for 40 min nnanocomposite.