BIOCHAR PRODUCED FROM PYROLYSIS OF OLIVE POMACE AS AN ADSORBENT FOR CR (VI) REMOVAL FROM AQUEOUS SOLUTIONS

Abstract: In this study, utilization of biochar obtained from pyrolysis of olive pomace as an adsorbent for removal of Cr (VI) from aqueous solution under different conditions. The adsorption experiments were implemented in batch process. The effects of various process parameters were investigated on the adsorption efficiency. The optimum removal conditions were determined as pH 3, time 30 min, concentration 10 mg L-1, dose 0.4 g and temperature 30 °C. The properties of biochar before and after adsorption were examined with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses. The adsorption performance of biochar was evaluated by Langmuir and Freundlich isotherm models by using different concentrations of Cr (VI) in the range of 10-80 mg L-1. Langmuir isotherm fitted to experimental data with higher accuracy and a maximum adsorption capacity of 4.9 mg g-1. The pseudo second order kinetic model gave a better fit with best correlation to the kinetic data. In the light of the results, it can be said that the biochar was successfully used as a low-cost and environmental friendly adsorbent for Cr (VI) removal from contaminated water.