Cargando…

Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model

[Image: see text] Adsorption kinetic equation has been derived assuming that the process follows the behavior of a heterogeneous chemical reaction at the solid–liquid interface. This equation is converted into the Langmuir isotherm at equilibrium and describes well the unsteady-state adsorption proc...

Descripción completa

Detalles Bibliográficos
Autores principales: Islam, Md Akhtarul, Chowdhury, Myisha Ahmed, Mozumder, Md. Salatul Islam, Uddin, Md. Tamez
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2021
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8190925/
https://www.ncbi.nlm.nih.gov/pubmed/34124471
http://dx.doi.org/10.1021/acsomega.1c01449
_version_ 1783705781910110208
author Islam, Md Akhtarul
Chowdhury, Myisha Ahmed
Mozumder, Md. Salatul Islam
Uddin, Md. Tamez
author_facet Islam, Md Akhtarul
Chowdhury, Myisha Ahmed
Mozumder, Md. Salatul Islam
Uddin, Md. Tamez
author_sort Islam, Md Akhtarul
collection PubMed
description [Image: see text] Adsorption kinetic equation has been derived assuming that the process follows the behavior of a heterogeneous chemical reaction at the solid–liquid interface. This equation is converted into the Langmuir isotherm at equilibrium and describes well the unsteady-state adsorption process. Based on that, a working equation has been developed, which gives adsorption-rate-constant independent of operating parameters including concentration. Also, a kinetic model expressed as a sum of first- and second-order systems available in the literature has been applied (modified with the interface reaction concept) to determine the adsorption rate constant. Both methods gave similar results. Three dimensionless numbers have been developed to determine and distinguish pseudo-first-order and pseudo-second-order kinetics justified from the viewpoint of chemical kinetics. It is shown that curve-fitting with a high correlation coefficient could validate an empirical kinetic model, but the fitted model parameters could not automatically be related to chemical kinetic parameters if the model itself is not grounded on well-defined chemical kinetics. Finally, it is concluded that the currently applied empirical approach could not provide reliable data for comparison among similar systems, while the Langmuir kinetic equation developed based on the concept of heterogeneous reaction would be a good basis for standardization of the method for adsorption system characterization.
format Online
Article
Text
id pubmed-8190925
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher American Chemical Society
record_format MEDLINE/PubMed
spelling pubmed-81909252021-06-11 Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model Islam, Md Akhtarul Chowdhury, Myisha Ahmed Mozumder, Md. Salatul Islam Uddin, Md. Tamez ACS Omega [Image: see text] Adsorption kinetic equation has been derived assuming that the process follows the behavior of a heterogeneous chemical reaction at the solid–liquid interface. This equation is converted into the Langmuir isotherm at equilibrium and describes well the unsteady-state adsorption process. Based on that, a working equation has been developed, which gives adsorption-rate-constant independent of operating parameters including concentration. Also, a kinetic model expressed as a sum of first- and second-order systems available in the literature has been applied (modified with the interface reaction concept) to determine the adsorption rate constant. Both methods gave similar results. Three dimensionless numbers have been developed to determine and distinguish pseudo-first-order and pseudo-second-order kinetics justified from the viewpoint of chemical kinetics. It is shown that curve-fitting with a high correlation coefficient could validate an empirical kinetic model, but the fitted model parameters could not automatically be related to chemical kinetic parameters if the model itself is not grounded on well-defined chemical kinetics. Finally, it is concluded that the currently applied empirical approach could not provide reliable data for comparison among similar systems, while the Langmuir kinetic equation developed based on the concept of heterogeneous reaction would be a good basis for standardization of the method for adsorption system characterization. American Chemical Society 2021-05-26 /pmc/articles/PMC8190925/ /pubmed/34124471 http://dx.doi.org/10.1021/acsomega.1c01449 Text en © 2021 The Authors. Published by American Chemical Society Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Islam, Md Akhtarul
Chowdhury, Myisha Ahmed
Mozumder, Md. Salatul Islam
Uddin, Md. Tamez
Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title_full Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title_fullStr Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title_full_unstemmed Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title_short Langmuir Adsorption Kinetics in Liquid Media: Interface Reaction Model
title_sort langmuir adsorption kinetics in liquid media: interface reaction model
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8190925/
https://www.ncbi.nlm.nih.gov/pubmed/34124471
http://dx.doi.org/10.1021/acsomega.1c01449
work_keys_str_mv AT islammdakhtarul langmuiradsorptionkineticsinliquidmediainterfacereactionmodel
AT chowdhurymyishaahmed langmuiradsorptionkineticsinliquidmediainterfacereactionmodel
AT mozumdermdsalatulislam langmuiradsorptionkineticsinliquidmediainterfacereactionmodel
AT uddinmdtamez langmuiradsorptionkineticsinliquidmediainterfacereactionmodel