DD	-	diffusion dialysis
A	[${\mathrm{m}}^2$]	area
c	$\left[\frac{\mathrm{mol}}{\mathrm{l}}\right]$	molar concentration
F	$\left[\frac{\mathrm{l}}{\mathrm{s}}\right]$	volumetric flow rate
FeCl2	[-]	iron chloride (II)
HCl	[-]	hydrochloric acid
$J_i$	$\left[\frac{\mathrm{mol}}{{\mathrm{m}}^2·\mathrm{s}}\right]$	molar flux
$J_w;J_{os};J_{dr}$	$\left[\frac{\mathrm{l}}{{\mathrm{m}}^2·\mathrm{s}}\right]$	volumetric flux
i	[-]	Van´t Hoff coefficient
IN	[-]	initial
m	$\left[\frac{\mathrm{mol}}{\mathrm{kg}}\right]$	molality
M	$\left[\frac{\mathrm{g}}{\mathrm{mol}}\right]$	molecular weight
$P_i$	$\left[\frac{\mathrm{m}}{\mathrm{s}}\right]$	diffusive permeability
$P_{os}$	$\left[\frac{\mathrm{l}}{\mathrm{bar}·{\mathrm{m}}^2·\mathrm{s}}\right]$	osmotic permeability
R	$\left[\frac{\mathrm{l}·\mathrm{bar}}{\mathrm{K}·\mathrm{mol}}\right]$	gas constant
RR	[%]	recovery ratio
T	[K]	temperature
U	$\left[\frac{\mathrm{m}}{\mathrm{s}}\right]$	overall mass transfer coefficient
V	$\left[\mathrm{l}\right]$	volume
v	$\left[\frac{\mathrm{m}}{\mathrm{s}}\right]$	linear velocity
ZnCl2	[-]	zinc chloride
$\beta$	[-]	hydration number
η	[%]	recovery efficiency
$v$	$\left[\frac{\mathrm{l}}{\mathrm{mol}}\right]$	molar volume
$\pi$	[bar]	osmotic pressure
$\varphi$	[-]	osmotic coefficient
Subscripts and Superscripts
ch	channel
d	diffusate
dr	drag
exp	experimental
f	feed
i	ith component (HCl or FeCl2 or ZnCl2)
m	membrane
max	maximum
mod	modelling
os	osmotic
r	retentate
s	solvent
t	time
tot	total
w	water