T. Dehgan, M. A. Gholami Sefidkouhi, M. Khoshravesh, N. Samadani Langroudi,
Volume 25, Issue 1 (5-2021)
In this research, the nitrate removal by beech leaves was investigated in batch and column systems. The batch experiment was performed to address the effect of pH, contact time, adsorbent dosage and initial nitrate ion concentration on the nitrate removal. The results showed that with an increase in pH, the removal efficiency and adsorption capacity were decreased and nitrate removal by millimeter and nano adsorbent beech leaves reached equilibrium 120 and 90 minutes after experiment, respectively. With an increase in the nitrate concentration, the removal efficiency was decreased from 59.2% to 39.7% and 82.1% to 69.9% for millimeter and the nanoparticles of Beech leaves, respectively. In fixed-bed column adsorption experiments, the flow rates of 5, 8 and 11 ml/min and the nitrate concentration of 15, 50 and 120 mg/L were studied. The results showed with an increase in the nitrate concentration from 15 to 120 mg/L, the saturation time was decreased from 240 to 150 and 360 to 270 minutes for millimeter and nanoparticles of Beech leaves, respectively. Thomas, Dose-response and Yoon-Nelson models were fitted to the results of the continuous experiments. The Thomas model fitted the experimental data with high accuracy. Compared to the adsorbents, nano-adsorbent had more adsorption capacity in the batch and column systems.
