The limiting-stage method in the dynamics of sorption processes. I. Regions of influence of internal and longitudinal diffusion in the case of dynamics limited by external diffusion kinetics

1980 ◽  
Vol 29 (8) ◽  
pp. 1191-1195
Author(s):  
E. V. Venitsianov
Keyword(s):  
Diffusion Kinetics ◽  
Longitudinal Diffusion ◽  
External Diffusion ◽  
Limiting Stage

scholarly journals Contribution to the Study of Phosphorus Adsorption Kinetics on the Superficial Sediments of a Recently Development Artificial Estuary: Vridi Channel (Côte d'Ivoire)

2021 ◽  
pp. 1-22
Author(s):  
N’da Samuel ◽  
Yao Marcel Konan ◽  
Trokourey Albert
Keyword(s):  
Experimental Data ◽  
Adsorption Kinetics ◽  
Molecular Diffusion ◽  
Cold Season ◽  
Kinetics Model ◽  
Diffusion Kinetics ◽  
Phosphorus Adsorption ◽  
External Diffusion ◽  
Us Epa ◽  
Superficial Sediments

The aim of this study is to characterize phosphates adsorption kinetics on the superficial sediments of Vridi channel from its new hydromorphology. So, three scenarios have been carried out taking account the different waters seasons of this estuary by using pH and temperature as relevant parameters. In the first scenario, the experiments carried out at pH = 8 and T = 20°C to simulate phosphates adsorption on these sediments in its great cold season. In the second, the experiments carried out at pH = 8 and T = 25° C to simulate phosphates adsorption on these substrates in its hot season and small cold season. In the third, the experiments carried out at pH = 7 and T = 30°C to simulate phosphates adsorption on these sediments in its flood season. The experiences were carried out according to US EPA/530/SW-87/006-F protocol. KH2PO4 solutions were used as phosphates synthetic solutions. The experimental data were modeling by Lagergeen kinetics model (pseudo-order 1), Blanchard kinetics model (pseudo-order 2), Elovich kinetics model, Weber and Morris kinetics model and, external diffusion kinetics model. The results have showed phosphates adsorption on these sediments increase in the experiments carried out at pH = 8 and T = 20°C to those carried out at pH = 7 and T = 30°C. All experimental data have been well modeling by Blanchard kinetics model. So, these phosphates adsorption kinetics are pseudo-order 2 and the chemisorption is the dominant mechanism. The results obtained by the experimental data modeling by Weber and Morris kinetics model and external diffusion kinetics model showed that this process is not limiting by the molecular diffusion process. The experimental data have been again well modeling by Elovich kinetics model. That has confirmed the chemisorption character of this adsorption, and showed this chemisorption is activated.

scholarly journals EXTERNAL DIFFUSION KINETICS OF MASS TRANSFER. FEATURES OF KINETICS OF ADSORPTION

2020 ◽  
Vol 0 (2) ◽  
pp. 49-56
Author(s):  
Y. Gumnitsky ◽  
D. Symak ◽  
V. Sabadash ◽  
V. Atamanyuk
Keyword(s):  
Mass Transfer ◽  
Diffusion Kinetics ◽  
Kinetics Of Adsorption ◽  
External Diffusion ◽  
Kinetics Of

External diffusion kinetics of the adsorption of anionic red 8C dye on glauconite

2013 ◽  
Vol 47 (2) ◽  
pp. 144-148 ◽  
Author(s):  
I. M. Petrushka ◽  
Ya. M. Gumnitskii ◽  
M. S. Malovanyi
Keyword(s):  
Diffusion Kinetics ◽  
External Diffusion ◽  
Kinetics Of

DIFFUSION KINETICS IN GOLD-AMORPHOUS GeTe4THIN FILMS

1981 ◽  
Vol 42 (C4) ◽  
pp. C4-975-C4-978 ◽  
Author(s):  
J. M. Mackowski ◽  
M. Bendali ◽  
P. Normandon ◽  
P. Kumurdjian
Keyword(s):  
Diffusion Kinetics

Na, K, Rb, and Cs exchange in heulandite single crystals; diffusion kinetics

1997 ◽  
Vol 82 (5-6) ◽  
pp. 517-525 ◽  
Author(s):  
Ping Yang ◽  
Jano Stolz ◽  
Thomas Armbruster ◽  
Mickey E. Gunter
Keyword(s):  
Single Crystals ◽  
Diffusion Kinetics

Kinetics of Methane-Oxidizing Biofilms for Degradation of Toxic Organics

1988 ◽  
Vol 20 (11-12) ◽  
pp. 167-173 ◽  
Author(s):  
S. E. Strand ◽  
R. M. Seamons ◽  
M. D. Bjelland ◽  
H. D. Stensel
Keyword(s):  
Chlorinated Hydrocarbons ◽  
Enzymatic Oxidation ◽  
Diffusion Kinetics ◽  
Toxic Compound ◽  
Biofilm Model ◽  
Uptake Rates ◽  
Substrate Diffusion ◽  
Toxic Organics ◽  
Competitive Substrate ◽  
Kinetics Of

The kinetics of methane-oxidizing bioreactors for the degradation of toxic organics are modeled. Calculations of the fluxes of methane and toxic chlorinated hydrocarbons were made using a biofilm model. The model simulated the effects of competition by toxics and mediane on their enzymatic oxidation by the methane monooxygenase. Dual-competitive-substrate/diffusion kinetics were used to model biofilm co-metabolism, integrating equations of the following form:where S1 and S2 are the local concentrations of methane and toxic compound, respectively, and r and K are the maximum uptake rates and Monod coefficients, and x is the distance into the biofilm.

Sign in / Sign up

Export Citation Format

Share Document