Langmuir parameters Langmuir isotherm activated carbon carbon nanotubes Q0(mg/mg) 0.0078 0.528 B(l/mg) 5.6363 0.0042 Correlation coefficient (R2) 0.9795 0.9839 Freundlich parameters Freundlich isotherm activated carbon carbon nanotubes Slope(1/n)  5.3023 0.0053 Intercept log k 0.0198 0.1913 Correlation coefficient (R2) 0.9755 0.9813

Table 2: The Freundlich and Langmuir parameters of adsorption isotherm models.