bed {PUPAK}

Non-Linear Boyd External Diffusion Model

Description

The Boyd External Diffusion Model is frequently applied to adsorption kinetic data to calculate the rate constant, assuming that film diffusion is the rate-limiting step in the first few minutes of the adsorption process. The film diffusion has a strong dependency on agitation. Boyd’s diffusion models are used in numerous adsorption studies mostly to determine the rate-controlling step (Viegas, Campinas, Costa, and Rosa, 2014).

Usage

bed(t, qt, qinf)

Arguments

t

the numerical value for contact time

qt

the numerical value for the amount adsorbed at time t

qinf

the numerical value for the amount adsorbed at infinite time. If this parameter is not defined, it will be estimated.

Value

the non-linear regression and the parameter estimation for the Boyd External Diffusion model

Author(s)

Jeff Ryan S. Magalong

Joshua Z. DelaCruz

Jeann M. Bumatay

Chester C. Deocaris

References

Boyd, G. E., Adamson, A. W., & Myers, L. S. (1947) <doi:10.1021/ja01203a066> The Exchange Adsorption of Ions from Aqueous Solutions by Organic Zeolites. II. Kinetics1. Journal of the American Chemical Society, 69(11), 2836-2848.

Viegas, R. M. C., Campinas, M., Costa, H., &; Rosa, M. J. (2014) <doi:10.1007/s10450-014-9617-9> How do the HSDM and Boyd's model compare for estimating intraparticle diffusion coefficients in adsorption processes. Adsorption, 20(5-6), 737-746.

Examples

t <- c(0,15,30,45,60,75,90,105,120)
qt <- c(0.000,3.718,3.888,4.102,4.274,4.402,4.444,4.488,4.616)
qinf <- 4.68
bed(t,qt,qinf)
bed(t,qt)