Asenic removal from groundwater using granular chitosan-titanium adsorbent
Chuanyong Jing , Zuben Xu , Yaqin Yu , Li Yan , Wei Yan
DOI:10.1016/j.jes.2021.05.028
Received April 16, 2021,Revised , Accepted May 18, 2021, Available online June 05, 2021
Volume 34,2022,Pages 202-209
Arsenic (As) contamination poses an urgent environmental risk, and its removal from groundwater remains a challenge due to the lack of efficient adsorbents. Herein, a novel granular chitosan-titanium (CS-Ti) adsorbent was fabricated by the sol-gel method. Batch experiments show that As(V) adsorption on CS-Ti followed the pseudo-second-order kinetic model, and the adsorption isotherm conformed to the Freundlich model with the correlation coefficient of 0.99. In situ FTIR spectra revealed that the CS-Ti adsorbent was composed of amorphous TiOx and chitosan by forming C-O-Ti and N-Ti bonds, and the amorphous TiOx was responsible for As(V) adsorption. Rapid small-scale column tests show that 165.6 μg/L of As in groundwater were effectively removed in approximately 126-bed volumes, and the spent adsorbents were regenerated with 0.01 mol/L NaOH and maintained the adsorption efficiency after four cycles. This study provides a simple and practical route to fabricate adsorbents for water treatment.
