scholarly journals The Removal of Uranium and Thorium from Aqueous Solutions Onto by-pass Cement Dust (BCD)

2016 ◽  
Vol 11 (2) ◽  
pp. 105
Author(s):  
Ali Omnia M. ◽  
El-Kashif H.H. ◽  
Sayed S.A. ◽  
Shalabi M.E.H.

<p>The adsorption behavior of uranium and thorium from aqueous solutions by By-pass cement dust (BCD) has been investigated by a batch technique. The uranium and thorium adsorption on BCD was studied as a function of initial concentration, weight of BCD, pH, shaking time and temperature. The uptake of uranium and thorium at the determined optimum conditions follows Freundlich isotherm. The adsorption control of both thorium and uranium are first order and uptake energy of activation E<sub>a</sub> =10 and 15 kJ/mol for thorium and uranium respectively. Thermodynamic parameters such as ΔH<sup>o</sup>, ΔS<sup>o</sup> and ΔG<sup>o</sup> were also investigated.</p>

2015 ◽  
Vol 12 (6) ◽  
pp. 3996-4008
Author(s):  
Hussein A Mohamed ◽  
Magdy A Wassel ◽  
Rabie S Farg ◽  
Hassan A Shehata ◽  
Aamal M Anwar

The object of this study is to assess the removal of Fe(III) ions from aqueous solutions onto modified chitosan. The effect of various parameters has been investigated by the following batch adsorption technique. The various variables studied include initial concentration of the adsorbate, agitation time, adsorbent dosage, kinetics, influence of temperature. The experimental data was fit well to the Freundlich isotherm. Thermodynamic parameters such as ΔH, ΔS and ΔG were calculated, indicating that the adsorption was spontaneous and endothermic nature.


2016 ◽  
Vol 12 (2) ◽  
pp. 3996-4008
Author(s):  
Hussein A Mohamed ◽  
Magdy A Wassel ◽  
Rabie S Farg ◽  
Hassan A Shehata ◽  
Aamal M Anwar

The object of this study is to assess the removal of Fe(III) ions from aqueous solutions onto modified chitosan. The effect of various parameters has been investigated by the following batch adsorption technique. The various variables studied include initial concentration of the adsorbate, agitation time, adsorbent dosage, kinetics, influence of temperature. The experimental data was fit well to the Freundlich isotherm. Thermodynamic parameters such as ΔH, ΔS and ΔG were calculated, indicating that the adsorption was spontaneous and endothermic nature.


2012 ◽  
Vol 66 (8) ◽  
pp. 1699-1707 ◽  
Author(s):  
A. K. Giri ◽  
R. K. Patel ◽  
P. C. Mishra

In this work, the biosorption of As(V) from aqueous solutions by living cells of Bacillus cereus has been reported. The batch biosorption experiments were conducted with respect to biosorbent dosage 0.5 to 15 g/L, pH 2 to 9, contact time 5 to 90 min, initial concentration 1 to 10 mg/L and temperature 10 to 40 °C. The maximum biosorption capacity of B. cereus for As(V) was found to be 30.04 at pH 7.0, at optimum conditions of contact time of 30 min, biomass dosage of 6 g/L, and temperature of 30 ± 2 °C. Biosorption data were fitted to linearly transformed Langmuir isotherms with R2 (correlation coefficient) &gt;0.99. Bacillus cereus cell surface was characterized using AFM and FTIR. The metal ions were desorbed from B. cereus using both 1 M HCl and 1 M HNO3. The pseudo-second-order model was successfully applied to predict the rate constant of biosorption.


2007 ◽  
Vol 95 (7) ◽  
Author(s):  
E. Metwally ◽  
R. O. Abdel Rahman ◽  
R. R. Ayoub

Hydrous titanium oxide was chemically synthesized and tested as adsorbent material for the removal of cesium, cobalt and strontium ions from chloride waste solutions using batch technique. The influences of pH, contact time, and temperature have been reported. The uptake of both strontium and cobalt ions was found to be greater than that of cesium and the apparent sorption capacity of each ion increases with increase in temperature. Thermodynamic parameters such as changes in Gibbs free energy (Δ


2011 ◽  
Vol 287-290 ◽  
pp. 1653-1658 ◽  
Author(s):  
You Ya Zhou ◽  
Zeng Guang Yan ◽  
Kinam Kim

The adsorption of p,p’-DDT onto expanded graphite (EG) in aqueous solutions was investigated under varying conditions of p,p’-DDT concentrations, adsorbent doses, pH, and contact time. The removal efficiency of p,p’-DDT from the aqueous solutions remained constant in a range of pH 2 to 10, and the thermodynamic data followed the type II adsorption isotherm characterized by a spontaneous process. At lower concentrations, adsorption equilibrium of p,p’-DDT onto EG was fitted to Freundlich isotherm. Dynamic modeling of the adsorption showed that the first order reversible kinetic model was held for the adsorption process within the range of experimental concentration. It was suggested that expanded graphite can be used for efficient removal of p,p’-DDT from water and wastewater.


2015 ◽  
Vol 93 (10) ◽  
pp. 1083-1087 ◽  
Author(s):  
Ali Issa Ismail

Graphene is a newly discovered material and is considered to be the new wonder material for many applications. The recent possibility of obtaining pure and fully characterized graphene opens the door to the study of the adsorption of toxic materials on graphene. The adsorption behavior of p-nitrophenol on graphene was studied in aqueous medium. The effect of each of pH, temperature, and dosage was emphasized. The highest calculated adsorption capacity of 4-nitrophenol was found to be 15.5 mg/g, assuming Langmuir fitting starting from 11.1 mg/g initial concentration at 298 K and pH = 6. Fitting the data using the Freundlich isotherm model predicted a favorable adsorption process (n > 1). The rise and saturation areas of the isotherms were fitted as pseudo first-order and pseudo second-order processes, respectively, with relatively good fit (k1 = 0.0023/s, k2 = 0.68 g mg−1 s−1). The thermodynamic properties indicated a spontaneous and exothermic process.


2017 ◽  
Vol 105 (3) ◽  
Author(s):  
Kadriye Esen Erden ◽  
Ramazan Donat

AbstractNatural sepiolite has been tested as a potential sorbent for the removal of Th(IV) from aqueous solutions by batch technique. Effects of various parameters on the adsorption process have been investigated. Under optimum conditions, Th(IV) was adsorbed with high adsorption efficiency. The results indicated that sorption of Th(IV) on sepiolite was strongly affected by pH values and temperature. The adsorption patterns of thorium on the sepiolite adsorbent followed the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The thermodynamic data (Δ


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Patience Mapule Thabede ◽  
Ntaote David Shooto ◽  
Thokozani Xaba ◽  
Eliazer Bobby Naidoo

The aim of the present study was to utilise pristine and magnetite-sucrose functionalized Nigella Sativa seeds as the adsorbents for the uptake of chromium(VI) and lead(II) ions from synthetic wastewater. Prestine Nigella Sativa seeds were labelled (PNS) and magnetite-sucrose functionalized Nigella Sativa seeds (FNS). The PNS and FNS composites were characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The FTIR analysis of both adsorbents revealed the presence of vibrations assigned to 1749 and 1739 cm-1 (-C=O) for ketonic group for both adsorbents. The amide (-NH) peak was observed at 1533 and 1527 cm-1 on FNS and PNS composites, respectively, whilst the carboxyl group (-COOH) were observed at 1408 cm-1 on both adsorbents. The XRD results of FNS and PNS composites showed a combination of spinel structure and y -Fe2O3 phase confirming the formation of iron oxide. The influence of operational conditions such as initial concentration, temperature, pH, and contact time was determined in batch adsorption system. The kinetic data of Cr(VI) and Pb(II) ions on both adsorbents was described by pseudo-first-order (PFO) model which suggested physisorption process. The sorption rate of Cr(VI) ions was quicker, it attained equilibrium in 20 min, and the rate of Pb(II) ions was slow in 90 min. Freundlich isotherm described the mechanism of Pb(II) ions adsorption on PNS and FNS composites. Langmuir best fitted the uptake of Cr(VI) ions on PNS and FNS. The results for both adsorbents showed that the removal uptake of Pb(II) ions increased when the initial concentration was increased; however, Cr(VI) uptake decreased when the initial concentration increased. The adsorption of Cr(VI) and Pb(II) ions on both adsorbents increased with temperature.


Author(s):  
Meruyert Kaygusuz ◽  
Cem Gök

In this study, fig leaves, zeolite and alginate were used to prepare a biocomposite for the adsorption of Pb(II) ions from aqueous solutions. Effects of various parameters on the biosorption process such as pH, temperature, initial lead concentration and contact time have been investigated. Maximum uptake of Pb(II) ions (85%) has been achieved at pH 6, with 25 mg/L of initial concentration and at a temperature of 288.15 K. Among the applied models, the data correlated well with Freundlich and D-R models and it was established that the biosorption was physical in nature. The amount of adsorbed lead per gram of sorbent was found to be 150.3 mg/g. Thermodynamic parameters showed the exothermic heat of biosorption and the feasibility of the process. Results have suggested that the prepared biosorbent possesses promising biosorption potential.


2012 ◽  
Vol 610-613 ◽  
pp. 1950-1953
Author(s):  
Zheng Jun Gong ◽  
Wenbo Zhou ◽  
Zhong Ping Qiu

In this study, removal of copper(Ⅱ) from aqueous solutions was examined using corn stalk. In the batch mode adsorption studies, the effects of initial pH and contact time on the copper(Ⅱ) adsorption by the corn stalk have been studied. The results show that: the pH 6.0 and contact time 8 hrs is optimum conditions of this absorption process when the dosage of corn stalk is 0.1g. In the isotherm studies, the Langmuir and Freundlich isotherm models were applied. The R2 of the Langmuir and Freundlich isotherm are 0.981 and 0.944 respectively. The Langmuir adsorption capacity Qmax is 54.05 mg/g. The goodness of fitness was obtained with the Langmuir and Freundlich adsorption isotherms.


Sign in / Sign up

Export Citation Format

Share Document