The modified rice husk no. 6 is used as the model adsorbent
to study the adsorption of paraquat, using various
initial paraquat concentrations. Table 2 presents the
equilibrium adsorption of paraquat, which increases from
113.8 to 231.2 mg/g-adsorbent with the initial concentration
from 36 to 120 ppm. Fig. 3 plots the Langmuir and
Freundlich correlations of paraquat adsorbed by the RHg-PMANa
adsorbent. Table 3 presents the corresponding
calculations. Since the standard deviation (SD) associated
with the non-linear regression are 0.0270 and 0.0632 for