Adsorption of Methylene blue onto hydrophobic activated carbon

Activated carbon (AC) was prepared from date palm leaflets using NaOH activation. AC oxidized concentrated HNO3 to produce activated (ON). Alkylamines including methylamine (M), dimethylamine (DM), ethylamine (E), diethylamine (DE), and diisopropylamine (DIP) were covalently immobilized onto ON ONM, ONDM, ONE, ONDE, ONDIP hydrophobic carbons, respectively. The surface area of (588 m2/g) decreased on oxidation with a further decrease functionalization. These carbons tested for methylene blue (MB) adsorption. Initial pH 7 found optimum the adsorption MB. show faster (except ONDE), than data following well pseudo-second-order kinetic model. rate increased temperature rise. activation energy, Ea, less 42 kJ/mol indicating physical Equilibrium follows L-type isotherm Langmuir capacity MB order > ONE ONDM ONM ONDE. Thermodynamic parameters indicate spontaneous endothermic Carbon reuse more efficient ONDIP,