Sedigheh Daroumi; Mohammad Ali Aroon; Ramin Yavari; taher yousefi; Hossein Ghasemi mobtaker
Abstract
In this study, the flat sheet membranes including the neat polyethersulfone (PES) and the mixed matrix membranes (MMMs) containing 20 wt. % polyethersulfone (PES) and various amounts of Fe3O4 nanoparticles were prepared using wet phase inversion and conventional casting methods. Manganese ion rejection ...
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In this study, the flat sheet membranes including the neat polyethersulfone (PES) and the mixed matrix membranes (MMMs) containing 20 wt. % polyethersulfone (PES) and various amounts of Fe3O4 nanoparticles were prepared using wet phase inversion and conventional casting methods. Manganese ion rejection and permeate flux as a performance evaluation of the prepared membranes was studied and compared. The characteristics of the fabricated membranes and the synthesized nanoparticles were fulfilled by transmission electron microscopy, field emission scanning electron microscopy and contact angle measurement. The operational parameters such as polymer concentration, pressure, pH, manganese ion concentration and time for manganese ion rejection and permeability were firstly optimized on the neat PES membrane. In the next steps, the performance of the fabricated MMMs containing various amount of Fe3O4 nanoparticles and PES (20%wt.) was evaluated and compared under these optimized conditions. Under the optimal conditions obtained for the rejection of manganese ions by neat PES, the fabricated MMMs had better performance than the neat PES membrane. Also, the results showed that the best performance of the prepared MMMs with the manganese rejection percentage of 89.3% and permeate flux of 28.7 L.m-2.h was found to belong to the PES membranes containing 0.1 wt.% of Fe3O4.
Behgam Rahmanivahid; Freshteh Naderi; Hamed Nayebzadeh
Abstract
In this paper, Fe3O4 and MgFe2O4 as magnetic samples were successfully synthesized by coprecipitation and combustion methods, respectively, to be used for adsorption of toxic methyl orange molecules from the aqueous solution. Characteristics of the synthesized samples were evaluated using various analyses. ...
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In this paper, Fe3O4 and MgFe2O4 as magnetic samples were successfully synthesized by coprecipitation and combustion methods, respectively, to be used for adsorption of toxic methyl orange molecules from the aqueous solution. Characteristics of the synthesized samples were evaluated using various analyses. The results of crystalline and surface bonding assessment confirmed the successful synthesis of both samples with an appropriate structure. Moreover, Fe3O4 presented higher magnetic properties and surface area as well as lower pore diameter than MgFe2O4 sample. However, the maximum adsorption of methyl orange was obtained for MgFe2O4 (56.54 mg/g) which was around three times of Fe3O4 in the same conditions. This may be related to larger pore diameter of MgFe2O4 and the ease of access to the internal surface of the adsorbent by the adsorbate molecules. Among the evaluated isotherms, the predicted Freundlich model showed well correlation with actual results of the adsorption process and the process could kinetically explained by the pseudo-second-order equation. Thermodynamic investigation of the process showed the adsorption of methyl orange was exothermic and spontaneous. The results revealed that MgFe2O4 sample (qmax = 181.34 mg/g) can be suggested as a good adsorbent for the removal of toxic dyes and water pollutants.
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