ADSORPTION OF REMAZOL BLACK RL AND REACTIVE YELLOW 145 FROM AQUEOUS SOLUTIONS BY PINE NEEDLES

Adsorption of Reactive Yellow 145 (RY145) and Remazol Black RL (RBRL) onto pine
needles (PN) was investigated with respect to initial dye concentrations, adsorbent dosage, and pH
in a batch manner. The obtained data in the study were described according to the Langmuir and
Freundlich isotherm models and the Langmuir model describes the experimental data very well
with a qmax value of 13.831 and 7.225 for RBRL and RY145 respectively. As the pH decreased,
adsorption density increased gradually and the highest adsorption density was obtained at pH 2 for
both adsorbents (91.57 and 64.77% for RBRL and RY145 respectively). Equilibrium adsorption
rates of 70.15% with RY145 and 86.72% with RBRL onto PN were observed at 90 min. In order
to better model the kinetics of adsorption, first order, pseudo second order and second order
models were applied. Among these models, the pseudo-second order kinetic model provided a
good correlation for the adsorption of RY145 and RBRL by PN with a R2> 0.999. Results showed
that pine needles have great potential to remove Reactive Yellow 145 (RY145) and Remazol
Black RL from aqueous solutions.