Page 48 - Separation process engineering

w , w B
A
width of chromatographic peak, s, min or hours
W

weight of the column per length, kg/m
x

deviation from the location of the peak maximum, dimensionless Eq. (18-79)
x l

deviation from peak maximum in length units, Eq. (18-80b)

x t

deviation from peak maximum in time units, Eq. (18-80a)
x

weight or mole fraction solute in liquid, kg solute/kg liquid or kmol solute/kmol
liquid, dimensionless
x
i
= c /c equivalent fraction of ion in solution, dimensionless
i T
X (z,t)
breakthrough
general solution for column breakthrough for linear isotherms, same units as c,
Eq. (18-72)
y

weight or mole fraction solute in gas, kg solute/kg gas, or kmol solute/kmol gas,
dimensionless

y i
= c /c equivalent fraction of ion on resin, dimensionless
Ri RT
z

axial distance in column, m or cm.
(Measured from closed end for PSA pressure change calculations)

Greek letters

β strong

ratio velocities of strong and weak solutes, Eq. (18-27), dimensionless
Δc

change in solute concentration, same units as c

ΔH ads
heat of adsorption, J/kg, cal/gmole, etc.

Δp A

change in partial pressure, kPa, atm, etc.
Δq

3
change in amount adsorbed, kmol/kg adsorbent, kg/kg adsorbent, kmol/m , or