Abstract
Besides adsorption rate constant, the half-life was also a basic factor that described the characteristics of adsorption kinetics. However, the direct prediction of the half-life was still a problem to be addressed urgently. In this work, the parameter τ was introduced into the pseudo-first-order (PFO), pseudo-second-order (PSO), pseudo-nth-order (PNO), and the corresponding fractal-like kinetic models (fractal-like PFO, fractal-like PSO, and fractal-like PNO) to directly predict the half-life by changing the boundary condition, i.e., the replacement of qt = 0, t = 0 by qt = qe/2, t = τ. The fitting performance of these kinetic models after modification was evaluated by nitrate adsorption on polyaniline-modified activated carbon (PAN/AC) and phosphate adsorption on zirconium-loaded Ca-montmorillonite. The results indicated that this type of model modifications did not influence the fitting performance and that the half-life was easily obtained only by the curve fitting. The practical significance of this work was to simultaneously predict the adsorption rate constant and half-life using the modified kinetic models.

Similar content being viewed by others
Abbreviations
- C 0 :
-
Concentration of adsorbate at initial time (mg L−1)
- C e :
-
Concentration of adsorbate at equilibrium (mg L−1)
- F :
-
Adsorption progress (F = qt/qe)
- h :
-
Fractal-like exponent (dimensionless)
- k 1 :
-
Pseudo-first-order rate constant (min−1)
- k 2 :
-
Pseudo-second-order rate constant (g mg−1 min−1)
- k n :
-
pseudo-nth-order rate constant (gn − 1 mg1 − n min−1)
- \( {k}_1^0 \) :
-
Fractal-like pseudo-first-order rate constant (minh − 1)
- \( {k}_2^0 \) :
-
Fractal-like pseudo-second-order rate constant (g mg−1 minh − 1)
- \( {k}_n^0 \) :
-
Fractal-like pseudo-nth-order rate constant (gn − 1 mg1 − n minh − 1)
- q e :
-
Amount of adsorbate uptake per unit mass of adsorbent at equilibrium (mg g−1)
- q t :
-
Amount of adsorbate uptake per unit mass of adsorbent at time t (mg g−1)
- t :
-
Adsorption time (min)
- τ :
-
Half-life (min)
References
Azizian S, Fallah RN (2010) A new empirical rate equation for adsorption kinetics at solid/solution interface. Appl Surf Sci 256:5153–5156
Bonilla-Petriciolet A, Mendoza-Castillo DI, Reynel-Ávila HE (2017) Adsorption processes for water treatment and purification. Springer Nature
Dadvar S, Tavanai H, Morshed M, Ghiaci M (2013) A study on the kinetics of 2-chloroethyl ethyl sulfide adsorption onto nanocomposite activated carbon nanofibers containing metal oxide nanoparticles. Sep Purif Technol 114:24–30
Foo KY, Hameed BH (2010) Insights into the modeling of adsorption isotherm systems. Chem Eng J 156:2–10
Georgieva VG, Tavlieva MP, Genieva SD, Vlaev LT (2015) Adsorption kinetics of Cr(VI) ions from aqueous solutions onto black rice husk ash. J Mol Liq 208:219–226
Guo X, Wang J (2019) A general kinetic model for adsorption: theoretical analysis and modeling. J Mol Liq 288:111100
Haerifar M, Azizian S (2012) Fractal-like adsorption kinetics at the solid/solution interface. J Phys Chem C 116:13111–13119
Haerifar M, Azizian S (2014) Fractal-like kinetics for adsorption on heterogeneous solid surfaces. J Phys Chem C 118:1129–1134
Hu Q, Liu Y, Feng C, Zhang Z, Lei Z, Shimizu K (2018) Predicting equilibrium time by adsorption kinetic equations and modifying Langmuir isotherm by fractal-like approach. J Mol Liq 268:728–733
Jia L, Yao X, Ma J, Long C (2017) Adsorption kinetics of water vapor on hypercrosslinked polymeric adsorbent and its comparison with carbonaceous adsorbents. Microporous Mesoporous Mater 241:178–184
Ma J, Shen Y, Shen C, Wen Y, Liu W (2014) Al-doping chitosan–Fe(III) hydrogel for the removal of fluoride from aqueous solutions. Chem Eng J 248:98–106
Marczewski AW (2010) Analysis of kinetic Langmuir model. Part I: integrated kinetic Langmuir equation (IKL): a new complete analytical solution of the Langmuir rate equation. Langmuir 26:15229–15238
Rouquerol J, Rouquerol F, Llewellyn P, Maurin G, Sing KS (2013) Adsorption by powders and porous solids: principles, methodology and applications. Academic press, London
Shen C, Shen Y, Wen Y, Wang H, Liu W (2011) Fast and highly efficient removal of dyes under alkaline conditions using magnetic chitosan-Fe(III) hydrogel. Water Res 45:5200–5210
Tseng RL, Wu PH, Wu FC, Juang RS (2014) A convenient method to determine kinetic parameters of adsorption processes by nonlinear regression of pseudo-nth-order equation. Chem Eng J 237:153–161
Wang J, Guo X (2020) Adsorption kinetic models: physical meanings, applications, and solving methods. J Hazard Mater 390:122156
Zou Y, Zhang R, Wang L, Xue K, Chen J (2020) Strong adsorption of phosphate from aqueous solution by zirconium-loaded Ca-montmorillonite. Appl Clay Sci 192:105638
Funding
The authors gratefully acknowledge the financial support from the Scientific Research Foundation (10912-KYQD2019-08165).
Author information
Authors and Affiliations
Corresponding author
Additional information
Responsible Editor: Philippe Garrigues
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Electronic supplementary material
ESM 1
(DOCX 4230 kb)
Rights and permissions
About this article
Cite this article
Hu, Q., Zhang, Z. Prediction of half-life for adsorption kinetics in a batch reactor. Environ Sci Pollut Res 27, 43865–43869 (2020). https://doi.org/10.1007/s11356-020-10228-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11356-020-10228-x


