4.2 Adsorption isotherm
As stated before, the experimental adsorption isotherms represent the
balance between adsorbent and adsorbate at equilibrium conditions.
Figure 3 shows the adsorption isotherm for trans -cyclooctene on
AgNO3/silica at 23˚C. Provided that the adsorption
isotherm obeys the Langmuir isotherm type, \(\frac{C_{B_{e}}}{q_{B}}\)versus \(C_{B_{e}}\)should represent a linear behavior. Furthermore,\(\frac{C_{B_{e}}}{q_{B}}\) versus \(C_{B_{e}}\) has been plotted, from
which it can be observed that \(\frac{C_{B_{e}}}{q_{B}}\) is a linear
function of \(C_{B_{e}}\). The results indicate that the adsorption of
TCO on AgNO3 obeys the Langmuir isotherm model and the
highest adsorption capacity was recorded at 43.089 mg/g at initial
concentration of 5.85 g/dm3.
[CHART][CHART]
Figure 3. Adsorption isotherm of trans-cyclooctene on the
AgNO3/SiO2 at 23˚C,
WAgNO3=0.175 g,\(\frac{\mathbf{C}_{\mathbf{\text{Be}}}}{\mathbf{q}_{\mathbf{\text{Be}}}}\mathbf{=17.515}\mathbf{C}_{\mathbf{B}_{\mathbf{e}}}\mathbf{+20.529,\ }\mathbf{R}^{\mathbf{2}}\mathbf{=0.965}\);
(a) nonlinearized form and (b) linearized form (Eq. 3.3 ), for
calculated parameters b and qBmax, see Table 1
Accordingly, the Langmuir model parameters, \(b\) and \(q_{B_{\max}}\),
have been calculated see Table 1.
Table 1 Langmuir isotherm parameter b and qBmaxfor TCO adsorption on AgNO3/silica at 296.15 K