Abstract
Maximum removal (94±1.2%) of 2, 4 dichlorophenol (50 mg.dm-3) was achieved on silica with agitation of 4 hours, at pH 8 and
42°C. The positive enthalpy (ΔH) and negative free energy values (ΔG315K) suggested the endothermic and a spontaneous nature
of sorption. The free energy of the process at all temperature was negative and increased with the increase in temperature. The
values of free energy suggested a spontaneous process where the spontaneity decreased with the rise in temperature. Positive
values of ΔS described the randomness and a greater stability of sorption process with no structural changes at the solid-solution
interface during the sorption. The data was subjected to Freundlich and Langmuir isotherms and the values of qe (mg.g-1), K1,ads
and K2,ads(min-1) demonstrated that pseudo first order model was not fit for process, whereas, the pseudo second order kinetic
model was best to describe the kinetics of process. The Elovich model and Intra particle diffusion kinetic model graph were best
to describe the kinetics for DCP. A comparative experimental data revealed that developed method might be employed for
removal of DCP from the aqueous industrial effluents before discharging them into water bodies.