Munasir Nasir; Yekti Purnama Utami; Nuhaa Faaizatunnisa; Lydia Rohmawati; Evie Suebah; Ahmad Taufiq; Ezza Syuhada Sazali
Abstract
This study aims to determine the effectiveness of the GO- Fe3O4/Psf membrane in filtering water contaminated with dyes and salt. The membrane was prepared using the phase inversion method, with variations in the composition of GO- Fe3O4 (0.25%, 0.50%, 0.75%, and 1.00%), with polysulfone as the polymer ...
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This study aims to determine the effectiveness of the GO- Fe3O4/Psf membrane in filtering water contaminated with dyes and salt. The membrane was prepared using the phase inversion method, with variations in the composition of GO- Fe3O4 (0.25%, 0.50%, 0.75%, and 1.00%), with polysulfone as the polymer material and NMP as a diluent. The dead-end filtration method is used to study the ability to repel dyes and salt molecules in water. Hydrophilicity (surface contact angle test) and morphology (SEM) to confirm the membrane profile. Furthermore, rejection and filtration performance tests were carried out on water contaminated with dye (methylene blue) and water containing salt through salt rejection, flow flux, and UV-VIS tests. The filtration test results showed that the membrane with a composition of 0.75% had a salt rejection percentage of 59.33% (the highest), and the lowest flow flux was 54.42 L.m-2.h-1. The dye filtering results (MB) showed better performance on the same membrane. It has been observed that the permeate is brighter than the other membranes. These results indicate that the membrane with a GO- Fe3O4 concentration of 0.75 wt.% is the most effective compared to other membranes in filtering water. The presence of Fe3O4 nanoparticles increases the efficiency and durability of graphene membranes in salt rejection by increasing the surface charge and selectively adsorbing salt ions.
Mohammad Reza Jalali Sarvestani; Roya Ahmadi
Abstract
In this study, the impact of doping graphene with silicon and germanium on the adsorption of Ag+ was evaluated by density functional theory. At the outset, the structures of silver, adsorbents and their derived products at ten different configurations were optimized geometrically. Then, IR and frontier ...
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In this study, the impact of doping graphene with silicon and germanium on the adsorption of Ag+ was evaluated by density functional theory. At the outset, the structures of silver, adsorbents and their derived products at ten different configurations were optimized geometrically. Then, IR and frontier molecular orbital calculations were implemented on them and some important parameters such as adsorption energy, Gibbs free energy changes, enthalpy variations, the thermodynamic equilibrium constant, specific heat capacity, chemical hardness, energy gap and electrophilicity were obtained and inspected. The achieved results indicate that by doping graphene with silicon and germanium the adsorption process has become more spontaneous, exothermic and experimentally feasible. The influence of temperature on the adsorption procedure was also checked out and the results indicate that 298.15 K is the optimum temperature for the desired process at all of the evaluated configurations. The HOMO-LUMO related parameters reveal that the pure and also doped nano-adsorbents are not appropriate sensing material in the construction of conductometric sensors but they can act as an eminent neutral ion carrier in the development of a potentiometric ion selective electrode for determination of silver (I) cations.