where Ce is the equilibrium concentration (mg/L) and qe the amount
adsorbed at equilibrium (mg/g). The Langmuir constants Qm (mg/g)
represent the monolayer adsorption capacity and b (L/mg) relates to
the heat of adsorption. A plot of Ce/qe versus Ce gives a straight line of
slope 1/Qm and intercepts 1/Qmb are shown in Fig. 6.