Limits...
A Linear Diffusion Model of Adsorption Kinetics at Fluid/Fluid Interfaces.

Staszak M - J Surfactants Deterg (2016)

Bottom Line: The proposed approach assumes the near interface, adsorptive layer which is described based on Fick's transient diffusion law.The solution to the model contains the estimation of effective diffusivities with adsorptive layer thickness as well.The experimental results of toluene/water + sodium dodecyl sulfate are presented and used for model verification.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical Technology and Engineering, Poznan University of Technology, Pl. Skłodowskiej-Curie 2, 60-965 Poznan, Poland.

ABSTRACT

The paper presents a new model for kinetically controlled adsorption at the fluid/fluid interface. The main purpose of the presented approach is to relate easy to estimate bulk surfactant concentration with Gibbs surface excess. Two adsorption isotherms are involved in the new model development: Frumkin and Szyszkowski isotherms. Additionally the Johannsen time profile of concentration in the adsorption layer is assumed and estimated in the model derivation. The proposed approach assumes the near interface, adsorptive layer which is described based on Fick's transient diffusion law. The solution to the model contains the estimation of effective diffusivities with adsorptive layer thickness as well. The experimental results of toluene/water + sodium dodecyl sulfate are presented and used for model verification.

No MeSH data available.


SDS concentration profile in the adsorptive sublayer solved using values from the Szyszkowski isotherm
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4764644&req=5

Fig12: SDS concentration profile in the adsorptive sublayer solved using values from the Szyszkowski isotherm

Mentions: The boundary condition at x = 0 applies that surfactant flux to the interface is equal to the change of the surface excess. The right-hand side of this condition is formulated using Eq. (22). The boundary condition at x = L describes surfactant transport with constant bulk concentration of surfactant. The initial condition applies no presence of surface active substance in adsorptive sublayer at time t = 0. This assumes that fresh interface is present at the beginning of the adsorption process. The solution to the initial-boundary problem stated is presented on the Fig. 12.Fig. 12


A Linear Diffusion Model of Adsorption Kinetics at Fluid/Fluid Interfaces.

Staszak M - J Surfactants Deterg (2016)

SDS concentration profile in the adsorptive sublayer solved using values from the Szyszkowski isotherm
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4764644&req=5

Fig12: SDS concentration profile in the adsorptive sublayer solved using values from the Szyszkowski isotherm
Mentions: The boundary condition at x = 0 applies that surfactant flux to the interface is equal to the change of the surface excess. The right-hand side of this condition is formulated using Eq. (22). The boundary condition at x = L describes surfactant transport with constant bulk concentration of surfactant. The initial condition applies no presence of surface active substance in adsorptive sublayer at time t = 0. This assumes that fresh interface is present at the beginning of the adsorption process. The solution to the initial-boundary problem stated is presented on the Fig. 12.Fig. 12

Bottom Line: The proposed approach assumes the near interface, adsorptive layer which is described based on Fick's transient diffusion law.The solution to the model contains the estimation of effective diffusivities with adsorptive layer thickness as well.The experimental results of toluene/water + sodium dodecyl sulfate are presented and used for model verification.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical Technology and Engineering, Poznan University of Technology, Pl. Skłodowskiej-Curie 2, 60-965 Poznan, Poland.

ABSTRACT

The paper presents a new model for kinetically controlled adsorption at the fluid/fluid interface. The main purpose of the presented approach is to relate easy to estimate bulk surfactant concentration with Gibbs surface excess. Two adsorption isotherms are involved in the new model development: Frumkin and Szyszkowski isotherms. Additionally the Johannsen time profile of concentration in the adsorption layer is assumed and estimated in the model derivation. The proposed approach assumes the near interface, adsorptive layer which is described based on Fick's transient diffusion law. The solution to the model contains the estimation of effective diffusivities with adsorptive layer thickness as well. The experimental results of toluene/water + sodium dodecyl sulfate are presented and used for model verification.

No MeSH data available.