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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Nanostructures
- نوع مقاله: Journal Article
- کلمات کلیدی: Cadmium,Graphene Oxide,Nanocomposite,Heteropoly metalate
- چکیده:
- چکیده انگلیسی: We developed a facile strategy for preparation of heteropoly metalate/graphene oxide nanocomposite as a new ion exchanger for cadmium ion removal from aqueous solution. The synthesized nanocomposite was characterized by X-ray powder diffraction (XRD), UV-Vis spectroscopy, FT-IR spectroscopy and Raman spectroscopy. Our findings indicated that the combination of heteropoly metalate nanoparticles with graphene oxide results in an excellent performance for cadmium ions removal of aqueous solution. The experimental data demonstrated that the adsorption isotherm fitted well by Langmuir model with maximum sorption capacity of 47.85 mg/g. The removal behavior of this compound was evaluated by various parameters such as contact time, concentration of metal ion, pH of solution and temperature. In addition, the effect of interfering cations on the cadmium adsorption is investigated. Dubinin–Radushkevich model represented physical sorption occurred as bold mechanism that is confirmed by thermodynamic parameters. Also, the obtained data of the recycling experiment presented excellent stability after 4 consecutive cycles. This study indicated heteropoly metalate supported graphene oxide with good performance for removal of cadmium can be used for treating polluted solution by other heavy metal.
- انتشار مقاله: 17-02-1396
- نویسندگان: Hanieh Fakhri,Ali Reza Mahjoub,Hassan Aghayan
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Graphene Oxide,Oxidative desulfurization,Dibenzothiophene,Porous materials,SBA-15,Heteropoly acids,UiO-66
- چکیده:
- چکیده انگلیسی: Three novel heterogeneous catalysts were prepared by immobilization of a synthesized cesium salt of 4-tungsto-8-molybdophosphoric acid (abbreviated as CW4Mo8) on well prepared and modified support materials of UiO-66, microsphere SBA-15 and Graphene Oxide (GO). The aim of this work was the investigation of the support effects on the Oxidative DeSulfurization (ODS) performance under a similar condition. These catalysts were characterized using FTIR, XRD, BET, BJH, N2 adsorption-desorption, SEM, and EDX methods. The Cs modification was performed to have an insoluble CW4Mo8 on the support materials. The Keggin structure of the synthesized CW4Mo8 and well immobilization on the supports were confirmed by the characterization results. A comparative examination was performed on the capability of these nanocomposites as catalyst-adsorbent in the ODS process. Dibenzothiophene (DBT) in n-hexane was used as an oil model. The examination results indicated the special impact of the support type on the catalyst design; High surface area and porosity, and functional group type significantly affected the efficiency of DBT oxidation and adsorption of DBTO2 from fuel by these catalysts. The maximum removal of 100 and 99% of DBT was achieved using CW4Mo8 supported on mesoporous SBA-15 (after 60 min) and UiO-66 (after 120 min) respectively. Furthermore, the best catalyst could be reused four times without a remarkable decrease in activity.
- انتشار مقاله: 27-01-1398
- نویسندگان: Azam Akbari,Hanieh Fakhri
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,ARSENIC,Langmuir isotherm,Al nanoparticles,Arc discharge
- چکیده:
- چکیده انگلیسی: The present study describes a novel procedure for As (V) removal from water using pure Al nanoparticles (AlNps) prepared by arc discharge technique. Some spectroscopic and microscopic techniques such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) corroborated the structure of the prepared nanoparticles. From TEM image, the average size of nanoparticles was nearly calculated 15 nm. To confirm the removal of arsenic, Inductive Coupled Plasma Optical Emission Spectroscopy (ICP-OES) was used. The effects of some parameters such as contact time, adsorbent dose, As (V) initial concentration, pH, and ionic strength were investigated. In optimum conditions, for a solution with the initial concentration of 30 mg/L of arsenic (V), the maximum removal (92%) took place after 3h at pH of 3. The adsorption followed the pseudo-first-order kinetic model.The equilibrium data fitted well to Langmuir adsorption isotherm which suggested monolayer adsorption. Adsorption capacity was calculated 55.5 mg/g through Langmuir isotherm which confirmed AlNps present an outstanding ability to remove As (V) not only due to a high surface area and small particle size but also because of their great inherent action.
- انتشار مقاله: 22-08-1394
- نویسندگان: Samira Poorsadeghi,Mohamadzaman Kassaee,Hanieh Fakhri,Maryam Mirabedini
- مشاهده