scholarly journals Application of Some Starch Hydrogels for the Removal of Mercury(II) Ions from Aqueous Solutions

2008 ◽  
Vol 26 (8) ◽  
pp. 563-579 ◽  
Author(s):  
A. Hashem ◽  
F. Ahmad ◽  
R. Fahad
Keyword(s):  
Aqueous Solutions ◽  
Water Retention ◽  
Graft Polymerization ◽  
Ph Value ◽  
Ceric Ammonium Nitrate ◽  
Factors Affecting ◽  
Freundlich Isotherms ◽  
Adsorption Data ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Three types of starch hydrogels were prepared via the graft polymerization of acrylonitrile, AN, onto maize starch using ceric ammonium nitrate, CAN, as the initiator, followed by saponification with sodium hydroxide. The prepared hydrogel samples were characterized by estimating their nitrogen and carboxy group contents, and by the application of FT-IR spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM); in addition, their water retention values, WRVs, were also determined. The feasibility of using these hydrogels to remove Hg(II) ions from aqueous solutions was examined. Factors affecting the adsorption of Hg(II) ions onto the starch hydrogels were studied, including the pH value of the solution, the contact time and the concentrations of the adsorbent and adsorbate. The present study has shown that the prepared hydrogels could be used effectively for the adsorption of Hg(II) ions from aqueous solutions. The adsorption data obtained obeyed the Langmuir and Freundlich isotherms. The adsorption of Hg(II) ions onto the starch hydrogels followed second-order kinetics. An examination was made of the mechanism for the adsorption of Hg(II) ions onto the starch hydrogels.

scholarly journals Preparation, Characterization and Utilization of Amidoximated Poly(AN/MAA)-grafted Alhagi Residues for the Removal of Zn(II) Ions from Aqueous Solution

2009 ◽  
Vol 27 (4) ◽  
pp. 363-382 ◽  
Author(s):  
A.A. Khalil ◽  
H.H. Sokker ◽  
A. Al-Anwar ◽  
A. Abd El-Zaher ◽  
A. Hashem
Keyword(s):  
Aqueous Solution ◽  
Hydroxylamine Hydrochloride ◽  
Factors Affecting ◽  
Monomer Composition ◽  
Freundlich Isotherms ◽  
Adsorption Temperature ◽  
Adsorption Data ◽  
Adsorption Processes ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Radiation grafting by the mutual method of methacrylic acid/acrylonitrile (MAA/AN) onto Alhagi residues in the presence of dimethylformamide (DMF) as a solvent is discussed. The factors affecting the radiation graft copolymerization were investigated. These included radiation dose, co-monomer composition and concentration. The grafted samples were characterized using FT-IR spectroscopy and scanning electron microscopy (SEM), as well as by the estimation of their nitrogen and carboxyl group contents. The grafted samples were then amidoximated by treatment with hydroxylamine hydrochloride in an alkaline medium. Such amidoximated poly(MAA/AN)-grafted Alhagi residues were utilized for the removal of Zn(II) ions from aqueous solution by adsorption and the factors affecting such adsorption processes were studied. These factors were the pH of the adsorbate solution, the adsorbent dosage, the contact time and the adsorption temperature. The adsorption data obeyed the Langmuir and Freundlich isotherms. The Langmuir adsorption capacity (Qmax) of the amidoximated poly(MAA/AN)-grafted Alhagi residues towards Zn(II) ions was found to be 212.76 and 344.8 mg/g at 30 °C and 50 °C, respectively. Similarly, the Freundlich constants, KF and 1/n, at 30 °C were found to be 21.47 and 0.3489, respectively. The study showed that amidoximated poly(MAA/AN)-grafted Alhagi residues were effective in the adsorption of Zn(II) ions from aqueous solutions. The thermodynamics parameters of the adsorption process, viz. ΔH0, ΔG0 and ΔS0, were evaluated. The results showed that the adsorption of Zn(II) ions onto amidoximated poly(MAA/AN)-grafted Alhagi residues was endothermic and spontaneous. The adsorption data followed second-order kinetics.

scholarly journals γ-Induced Graft Copolymerization onto Cellulosic Fabric Waste for Cationic Dye Removal

2005 ◽  
Vol 23 (6) ◽  
pp. 455-466 ◽  
Author(s):  
A. Hashem ◽  
H.H. Sokker ◽  
E.S. Abdel Halim ◽  
A. Gamal
Keyword(s):  
Methylene Blue ◽  
Graft Copolymerization ◽  
Monomer Concentration ◽  
Maximum Adsorption Capacity ◽  
Factors Affecting ◽  
Freundlich Isotherms ◽  
Adsorption Data ◽  
Ft Ir ◽  
Cellulosic Fabric ◽  
Ft Ir Spectroscopy

Radiation grafting of itaconic acid (IA) onto cellulosic fabric in the presence of dimethylformamide (DMF) as a solvent by the mutual method is discussed. Factors affecting the radiation graft copolymerization were investigated. These factors include the radiation dosage, the monomer concentration and the solvent. The grafted samples were characterized using FT-IR spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Utilization of the grafted cellulosic fabric waste in the removal of Methylene Blue (MB) from aqueous solution was examined. The adsorption data showed that the maximum adsorption capacity of Methylene Blue onto grafted cellulosic fabric waste was 38 mg/g. The adsorption data also obeyed the Langmuir and Freundlich isotherms.

Nano-ZrO2/TiO2 Impregnated Orange Wood Sawdust and Peach Stone Shell Adsorbents for Cr (VI) Removal

2020 ◽  
Vol 16 (7) ◽  
pp. 880-892
Author(s):  
Şerife Parlayıcı ◽  
Kübra Tuna Sezer ◽  
Erol Pehlivan
Keyword(s):  
Contact Time ◽  
Ph Value ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Wood Sawdust ◽  
Adsorption Data ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Equilibrium Status

Background: In this work, Cr (VI) adsorption on nano-ZrO2๏TiO2 impregnated orange wood sawdust (Zr๏Ti/OWS) and nano-ZrO2๏TiO2 impregnated peach stone shell (Zr๏Ti/PSS) was investigated by applying different adsorption parameters such as Cr (VI) concentrations, contact time, adsorbent dose, and pH for all adsorbents. Methods: The adsorbents were characterized by SEM and FT-IR. The equilibrium status was achieved after 120 min of contact time and optimum pH value around 2 were determined for Cr (VI) adsorption. Adsorption data in the equilibrium is well-assembled by the Langmuir model during the adsorption process. Results: Langmuir isotherm model showed a maximum adsorption value of OWS: 21.65 mg/g and Zr๏Ti/OWS: 27.25 mg/g. The same isotherm displayed a maximum adsorption value of PSS: 17.64 mg/g, and Zr๏Ti/PSS: 31.15 mg/g. Pseudo-second-order kinetic models (R2=0.99) were found to be the best models for describing the Cr (VI) adsorption reactions. Conclusıon: Thermodynamic parameters such as changes in ΔG°, ΔH°, and ΔS° have been estimated, and the process was found to be spontaneous.

Fast Removal of Cu (II) from Aqueous Solutions by PET Nanofibrous Membrane Modified with Acryamide

2013 ◽  
Vol 750-752 ◽  
pp. 1343-1346 ◽  
Author(s):  
Xiao Cui Dong ◽  
Ding Cao ◽  
Yan Shi ◽  
Zhi Feng Fu
Keyword(s):  
Aqueous Solutions ◽  
Ph Value ◽  
Membrane Surface ◽  
Nanofibrous Membrane ◽  
Maximum Adsorption Capacity ◽  
Element Analysis ◽  
Equilibrium Studies ◽  
Poly Ethylene Terephthalate ◽  
Ft Ir ◽  
Poly Ethylene

A novel nanofibrous membrane was used for removing Cu (II) from aqueous solutions. The poly (ethylene terephthalate) (PET) membranes were fabricated by electrospinning, and then grafted with acrylamide (AM) on the surface. The morphologies of the nanofiber was characterized by SEM, meanwhile, the chemical composition and element analysis on the membrane surface were measured by FT-IR and XPS, respectively. The Cu (II) adsorption experiment investigated the adsorption performance related to the pH value on. Equilibrium studies show that the adsorption process follows Langmuir model and the maximum adsorption capacity was estimated to be 183.25 [mg/g].

scholarly journals Adsorption of Reactive Black 5 on Synthesized Titanium Dioxide Nanoparticles: Equilibrium Isotherm and Kinetic Studies

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Majeed A. Shaheed ◽  
Falah H. Hussein
Keyword(s):  
Titanium Dioxide ◽  
Aqueous Solutions ◽  
Titanium Dioxide Nanoparticles ◽  
Kinetic Studies ◽  
Second Order ◽  
Reactive Black 5 ◽  
Adequate Model ◽  
Factors Affecting ◽  
Freundlich Isotherms ◽  
Pseudo Second Order

The synthesized titanium dioxide nanoparticles (TiO2-NPs) were used as adsorbent to remove reactive black 5 (RB 5) in aqueous solution. Various factors affecting adsorption of RB 5 aqueous solutions such as pH, initial concentration, contact time, dose of nanoparticles, and temperature were analyzed at fixed solid/solution ratio. Langmuir and Freundlich isotherms were used as model adsorption equilibrium data. Langmuir isotherm was found to be the most adequate model. The pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were used to describe the adsorption kinetics. The experimental data was fitted to pseudo-second-order kinetics. The thermodynamic parameters such as Gibbs-free energy, enthalpy, and entropy changes were determined. These parameters indicated the endothermic and spontaneity nature of the adsorption. The results demonstrated the fact that the TiO2-NPs are promising adsorbent for the removal of RB 5 from aqueous solutions.

scholarly journals Preparation of Nanochitosan as an Effective Adsorbent for Removal of Pb (II) From Aqueous Solution

2019 ◽  
Author(s):  
Camellia Zareie ◽  
Saeideh Kholghi Eshkalak ◽  
Ghasem Najafpour Darzi ◽  
Mazyar Sharifzadeh baei ◽  
Habibollah Younesi ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Ph Value ◽  
Sorption Process ◽  
Sorption Data ◽  
Kinetics Of Adsorption ◽  
Force Microscopy ◽  
Freundlich Isotherms ◽  
Atomic Force ◽  
Pseudo Second Order ◽  
Sorption Parameters

In this work, nanochitosan (NC) was prepared through ionic gelation using low-molecular-weight chitosan and maleic acid (MA). The synthesized NC was charac¬terized by means of Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). In the course of preparation, the particle size of the material was strongly depended on the parameters such as chitosan concentration and pH of the solution. By controlling the above parameters, NC with the size of smaller than 100 nm was prepared. The chitosan and prepared NC were used for the adsorption of Pb (II) from aqueous solutions in a batch system. Among the sorption parameters, pH showed the strongest effect on the sorption process and maximum Pb (II) removal was obtained at pH value of 6. The pseudo-first-order and pseudo-second-order were used to track the kinetics of adsorption process. Langmuir and Freundlich isotherms were subjected to sorption data to estimate the sorption capacity. NC proved to be an excellent adsorbent with remarkable capacity to remove Pb (II) ions from the aqueous solutions at various concentrations. The NC also showed incredible performance with a comparatively easier preparation process than other reported work.

Study on Fly Ash for Oil-Containing Wastewater Treatment

2013 ◽  
Vol 448-453 ◽  
pp. 1408-1411
Author(s):  
Dan Fu
Keyword(s):  
Wastewater Treatment ◽  
Fly Ash ◽  
Langmuir Isotherm ◽  
Contact Time ◽  
Ph Value ◽  
Adsorption Properties ◽  
Experimental Results ◽  
Freundlich Isotherms ◽  
Langmuir And Freundlich Isotherms ◽  
Adsorption Data

In this paper, the adsorption properties of oil-containing wastewater on Fly Ash （FA）were investigated. The effects of contact time, adsorbent dosage, pH value and the temperature were examined. The equilibrium adsorption data are analyzed using Langmuir and Freundlich isotherms. The Langmuir isotherm fits the experimental results well. The study indicates that FA is a potential adsorbent for oil-containing wastewater treatment.

scholarly journals Removal of aniline from aqueous solutions by activated carbon coated by chitosan

2015 ◽  
Vol 5 (4) ◽  
pp. 610-618 ◽  
Author(s):  
Qian Liu ◽  
Lujie Zhang ◽  
Pan Hu ◽  
Ruihua Huang
Keyword(s):  
Activated Carbon ◽  
Aqueous Solutions ◽  
Ph Value ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Order Kinetic ◽  
Factors Affecting ◽  
Adsorbent Dosage ◽  
Wide Range ◽  
Carbon Coated

In this work, activated carbon (AC) coated by chitosan was synthesized and characterized by Fourier transform infrared spectrophotometer and scanning electron microscope (SEM) techniques. The removal of aniline from aqueous solutions by AC coated by chitosan was investigated. The factors affecting the adsorption of aniline onto AC coated by chitosan, including the ratio of AC to chitosan, adsorbent dosage, pH value of solution, initial aniline concentration, and contact time were evaluated. These results showed that the optimum operating conditions were: the ratio of AC to chitosan = 0.5, adsorbent dosage = 0.2 g, and the adsorption of aniline from aqueous solutions had better removal in the concentration range of 20–50 mg/L. This adsorbent allowed high removal toward aniline in a wide range of pH. The equilibrium time was 100 minutes. The Freundlich model exhibited better correlation of the equilibrium adsorption data. The pseudo-second-order kinetic equation could better describe the kinetic behavior of aniline adsorption.

scholarly journals Study of the effectiveness of the third generation polyamideamine and polypropylene imine dendrimers in removal of reactive blue 19 dye from aqueous solutions

2018 ◽  
Vol 5 (4) ◽  
pp. 197-203 ◽  
Author(s):  
Sepideh Sadeghi ◽  
Ghazal Raki ◽  
Asrin Amini ◽  
Nezamaddin Mengelizadeh ◽  
Mohammad Mehdi Amin ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Synthetic Wastewater ◽  
Third Generation ◽  
Freundlich Isotherms ◽  
The Third ◽  
Reactive Blue 19 ◽  
Adsorption Data ◽  
Poly Propylene

Background: Dye and colored materials cause health risks in water and therefore, must be removed from water supplies and wastewater. The aim of this study was to evaluate the effectiveness of the third generation poly(amidoamine) (PAMAM) and poly (propylene imine) dendrimers (PPI-G3) in the removal of reactive blue 19 (RB19) dye from aqueous solutions and determine the optimum conditions for the removal. Methods: This study was performed in a laboratory and batch scale. In this study, synthetic wastewater was examined with three different concentrations of RB19 (25, 50, and 100 mg/L), different pHs (3, 7, and 10), various amounts of dendrimer (0.4, 0.8, 1.2, and 1.6 g/L), and at different times (15, 30, and 60 minutes) during the adsorption process. The remaining amount of dye was measured by spectrophotometer at 592 nm wavelength. Langmuir and Freundlich isotherms were also tested. Results: The results showed that by increasing the reaction time and adsorbent dosage, the rate of dye removal increased while by increasing the initial dye concentration and pH, the dye removal efficiency was significantly decreased. In this study, with increase of pH from 3 to 10, dye removal efficiency at a concentration of 25 mg/L, decreased from 72% to 20% and 88% to 17% by PAMAM and PPI dendrimers, respectively. Excel software was used for data analysis. Conclusion: Both adsorbents had a good dye removal efficiency, but PPI dendrimer was more effective in removing RB19. Adsorption data followed the Langmuir isotherm.

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