Assessment of the adsorption kinetics, equilibrium and thermodynamic for the potential removal of reactive red dye using eggshell biocomposite beads

Elkady, M. F.; Ibrahim, Amal M.; El-Latif, Mona M. Abd

doi:10.1016/j.desal.2011.05.063

Cited by 197 publications

(88 citation statements)

References 60 publications

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“…The values of k id,1 are larger than k id,2 at any CO 2 partial pressure indicating that film diffusion of CO 2 molecules towards the carbon surfaces was relatively fast [60].…”

Section: Rate-limiting Adsorption Stagementioning

confidence: 97%

Kinetics of CO2 adsorption on cherry stone-based carbons in CO2/CH4 separations

Álvarez-Gutiérrez

Gil

Rubiera

et al. 2017

Chemical Engineering Journal

157

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Most practical applications of solids in industry involve porous materials and adsorption processes. A correct assessment of the equilibrium and kinetics of adsorption is extremely important for the design and operation of adsorption based processes. In our previous studies we focused on the evaluation of the equilibrium of CO 2 /CH 4 adsorption on cherry stone-based carbons. In the present paper the kinetics of adsorption of CO 2 on two cherry stone-based activated carbons (CS-H 2 O and CS-CO 2 ), previously prepared in our laboratory, has been evaluated by means of transient breakthrough experiments at different CO 2 /CH 4 feed concentrations, at atmospheric pressure and 30 ˚C. A commercial activated carbon, Calgon BPL, has also been evaluated for reference purposes. Three models have been applied to estimate the rate parameters during the adsorption of CO 2 on these carbons, pseudo-first, pseudo-second and Avrami´s fractional order kinetic models. Avrami´s model accurately predicted the dynamic CO 2 adsorption performance of the carbons for the different feed gas compositions. To further investigate the mechanism of CO 2 adsorption on CS-H 2 O, CS-CO 2 and Calgon BPL, intra-particle diffusion and Boyd´s film-diffusion models were also evaluated. It was established that mass transfer during the adsorption of CO 2 from CO 2 /CH 4 is a diffusion-based process and that the main diffusion mechanisms involved 2 are intra-particle and film diffusion. At the initial stages of adsorption, film diffusion resistance governed the adsorption rate, whereas intra-particle diffusion resistance was the predominant factor in the following stages of adsorption.

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“…The values of k id,1 are larger than k id,2 at any CO 2 partial pressure indicating that film diffusion of CO 2 molecules towards the carbon surfaces was relatively fast [60].…”

Section: Rate-limiting Adsorption Stagementioning

confidence: 97%

Kinetics of CO2 adsorption on cherry stone-based carbons in CO2/CH4 separations

Álvarez-Gutiérrez

Gil

Rubiera

et al. 2017

Chemical Engineering Journal

157

View full text Add to dashboard Cite

show abstract

“…The thickness of the boundary layer in the second portion that corresponds to the intra-particle diffusion (C 2 ) is larger than that of the first portion that concerned the film diffusion (C 1 ). Consequently, the values of the intra-particle diffusion rates k d2 are smaller than the film diffusion rates k d1 (Elkady et al 2011). That gives prediction that the humic acid removal process may be controlled by the intraparticle diffusion (Elkady et al 2011;Abd El-Latif and Ibrahim 2010).…”

Section: Adsorption Kineticmentioning

confidence: 94%

“…The pseudo-second-order model is based on the assumption that the rate-limiting step may be chemical sorption or chemisorption involving valence forces through sharing or exchange of electrons between sorbent and sorbate. It is assumed that the sorption capacity is proportional to the number of active sites occupied on the sorbent, then the kinetic rate law can be written as follows (Kamari et al 2009;Ngah et al 2011;Tao et al 2010;Wang et al 2011;Zhang and Bai 2003;Bhaumik et al 2012;Elwakeel and Yousif 2010;Gupta and Rastogi 2008;Gupta et al 2010;Kose and Kivanc 2011;Ehrampoush et al 2011;Chen et al 2010;Ugurlu et al 2005;Okoye et al 2010;Wang et al 2008b;Elkady et al 2011):…”

Section: Adsorption Kineticmentioning

confidence: 99%

“…Therefore, to analyze the mechanism of removal process, the intra-particle diffusion model can be used. The equation can be described as follow (Tao et al 2010;Bhaumik et al 2012;Elwakeel and Yousif 2010;Chen et al 2010;Ugurlu et al 2005;Okoye et al 2010;Elkady et al 2011):…”

Section: Adsorption Kineticmentioning

confidence: 99%

“…The pseudo-first-order rate expression was evaluated with the following equation (Kamari et al 2009;Ngah et al 2011;Tao et al 2010;Wang et al 2011;Zhang and Bai 2003;Bhaumik et al 2012;Elwakeel and Yousif 2010;Rastogi 2008, Gupta et al 2010;Kose and Kivanc 2011;Ehrampoush et al 2011;Chen et al 2010;Ugurlu et al 2005;Okoye et al 2010;Wang et al 2008b;Elkady et al 2011): log ðq e À q t Þ ¼ log q e À k=2:303:t ð6Þ…”

Section: Adsorption Kineticmentioning

confidence: 99%

See 2 more Smart Citations

Removal of humic acid from peat water using untreated powdered eggshell as a low cost adsorbent

Zulfikar

Novita²,

Hertadi

et al. 2013

Int. J. Environ. Sci. Technol.

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The main objective of this study is to investigate the possibility of powdered eggshell used as an adsorbent material for removal of humic acid from peat water. The influences of contact time, dose of eggshells, pH, and temperature were the factors considered in the removal processes of humic acid from peat water. In addition, adsorption isotherms of humic acid onto the powdered eggshell were also evaluated with the Langmuir and Freundlich approximations. Our results showed that the equilibrium of the process was eventually established after 60 min of the contact time, and also found that using 5 g of the powdered eggshell nearly 95 % of humic acid has been successfully removed from the peat water. The removal of humic acid gave better result when it was conducted at low pH, and it was almost unaffected the temperatures variation. The data was well fitted to Freundlich isotherm with the correlation coefficient of not \0.999, and could uptake the humic acid about 126.58 mg/g at pH 4.01, estimated from the Langmuir model. The kinetic experimental data proportionally correlated with the pseudo-second-order kinetic model with a rate constant in the range of 0.016-0.112 g mg -1 min -1 , while intra-particle-diffusion were the main rate determining step in the humic acid removal process. The powdered eggshell investigated in this study, thus, exhibited as a high potential adsorbent for the removal of humic acid from peat water.

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