# permcoef: Calculates permeability coefficients In transmem: Treatment of Membrane-Transport Data

## Description

Permeability coefficients across a membrane as derived from integrated Fick's law can be obtained from transport data according to the equation

\ln{\Bigg(\frac{C}{C^0}\Bigg)}= -\frac{P~a}{V}t

where P is the permeability coefficient, a is the membrane exposed area, C and C^0 are the species concentrations at any time and at initial time in the feed phase, respectively, and V is solution volume.

## Usage

 1 2 permcoef(trans, vol, area, units = c("cm^3", "cm^2", "h"), conc0 = NULL, plot = FALSE) 

## Arguments

 trans Data frame with the complete transport information of interest species. Must be generated using conc2frac. vol Volume of the feed solution. area Membrane exposed area to the feed solution. units Units in which volume, area and time are provided. Volume and area are function's parameters while the time is extracted from the trans data frame. conc0 Initial concentration of the species in the feed solution. The value may be extracted from transport information if the data frame provided in trans is not normalized. See conc2frac for details. plot logical default to TRUE. Should the plot be made?

## Details

Species concentration units may be arbitrary as long as the permeability coefficient is calculated using the change in concentration ratio which is, as most ratios, adimensional

## Value

A numeric vector with the permeability coefficient and it's standard uncertainty from the regression. Units are meters per second.

## Author(s)

Cristhian Paredes, craparedesca@unal.edu.co

Eduardo Rodriguez de San Miguel, erdsmg@unam.mx

transmem documentation built on July 1, 2020, 10:38 p.m.