Pranjal Saikia; Ananta Saikia; Binoy Kumar Saikia
Abstract
Removal of heavy metals from waste water is a need of the hour. Titanium dioxide (TiO2) nanoparticles were functionalized using succinic anhydride (SA) and adsorption of copper (II) on SA functionalized TiO2 nanoparticles (TiOSA) was carried out. The adsorption of Cu (II) on TiOSA was estimated with ...
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Removal of heavy metals from waste water is a need of the hour. Titanium dioxide (TiO2) nanoparticles were functionalized using succinic anhydride (SA) and adsorption of copper (II) on SA functionalized TiO2 nanoparticles (TiOSA) was carried out. The adsorption of Cu (II) on TiOSA was estimated with respect to pH, contact time and adsorbent dose. The study confirms the best removal of Cu (II) using the said adsorbent is at pH 8. The Cu (II) concentration can be reduced to less than 1.1 mg/L at contact time of 180 min with initial 15 mg/L Cu (II) concentration using adsorbent dose of 0.6 g/50 mL. The study reveals that the adsorption process preferably follows the Langmuir isotherm model. Also, the thermodynamic parameters like entropy change (∆S°), enthalpy change (∆H°) and free energy change (∆G°) were calculated for the adsorption process. The pseudo-second order kinetic model was found to be better fitted to the adsorption.
Elham Shokri; Reza Yegani
Abstract
In this work, polysulfone (PSf) mixed matrix membranes were prepared by incorporating modified montmorillonite with lysine amino acid (MMT-Lys) for arsenic removal from water. Different tests including XRD, zeta potential, FE-SEM, contact angle, and pure water flux (PWF) were carried out to characterize ...
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In this work, polysulfone (PSf) mixed matrix membranes were prepared by incorporating modified montmorillonite with lysine amino acid (MMT-Lys) for arsenic removal from water. Different tests including XRD, zeta potential, FE-SEM, contact angle, and pure water flux (PWF) were carried out to characterize modified MMT and fabricated mixed matrix membranes. XRD analysis showed that MMT was successfully modified with Lys and its zeta potentials transferred from negative to positive after modification. Positive charge of MMT-Lys made it proper for anionic arsenic removal from water. The obtained results showed that pure water flux and surface hydrophilicity of the membranes improved as MMT-Lys contents increased from 0 to 1.5 wt.%. The batch adsorption of fabricated membranes as a function of arsenic initial concentration and solution pH was investigated. The removal efficiency was increased with increasing the arsenic initial concentration; however it was decreased with increasing pH of solution. The results also revealed that the arsenic adsorption was most favorable in the neutral pH. Moreover, membrane reusability of the PSf/MMT-Lys (1.5 wt.%) membrane was assessed by conducting five cycles of adsorption-desorption experiments in dead-end filtration. The obtained results showed the applicability of the prepared membrane for multiple cycles.
Zahra hassanzadeh Siahpoosh; Majid Soleimani
Abstract
This investigate presents the extraction-preconcentration of Lead, Cadmium, and Nickel ions from water samples using Ghezeljeh montmorillonite nanoclay or “Geleh-Sar-Shoor” (means head-washing clay) as a natural and native new adsorbent in batch single element systems. The Ghezeljeh clay ...
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This investigate presents the extraction-preconcentration of Lead, Cadmium, and Nickel ions from water samples using Ghezeljeh montmorillonite nanoclay or “Geleh-Sar-Shoor” (means head-washing clay) as a natural and native new adsorbent in batch single element systems. The Ghezeljeh clay is categorized by using Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy-Energy Dispersive Spectrometer Operating (SEM-EDS), X-ray Diffractometry (XRD), X-ray Fluorescence (XRF), Cation Exchange Capacity (CEC) measurements, Surface property valuation (SBET) by the BET method from nitrogen adsorption isotherms and Zeta potential. According to BET theory, the specific surface area of Ghezeljeh nanoclay was computed as 19.8 m2 g-1 whereas the cation exchange capacity was determined as 150 meq (100 g-1). The results of XRD, FT-IR, XRF, zeta potential, BET surface area and CEC of the Ghezeljeh clay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of clay, it can be seen that the distance between the plates is nm level. For all three ions, the limit of detection, the limit of quantification, dynamic linear range, preconcentration factor, and the adsorption capacity were obtained. The result of several interfering ions was considered. The Ghezeljeh nanoclay as a new adsorbent and experimental method were effectively used for the extraction of heavy metals (Lead, Cadmium, and Nickel) in a variety of real water samples.