Adsorption and recovery of lithium ions from groundwater using date pits impregnated with cellulose nanocrystals and ionic liquid
Sara A. Wahib, Dana A. Da’na, Nabil Zaouri, Yousef M. Hijji, Mohammad A. Al‐Ghouti
Abstract
The study aims to prepare a novel low-cost and environmentally friendly adsorbent by using date pits (DP) impregnated with cellulose nanocrystals (CNCs) and ionic liquid (IL), named [email protected] The batch adsorption of lithium onto [email protected] and DP were studied at different pH values, initial lithium concentrations, and temperatures. The thermodynamics constants of the adsorption process showed that the [email protected] was exothermic, did not favor a high level of disorder, and spontaneous in nature. At pH 6, there is a significant increase in the removal efficiency where it increased to 90%. This also could be explained by the fact that electrostatic attraction forces and hydrogen bonding existed between the protonated Li+ and the less protonated [email protected] adsorbent surface, which enhanced the percentage of Li+ removal. A strong inter- and intra-hydrogen bonding (O-H) stretching absorption is seen at 3311 cm−1 that occurs in cellulose components. In conclusion, the [email protected] in comparison to the DP confirmed exceptional results proving that the modification enhanced the remediation of the Li+ from water. Furthermore, the selectivity of [email protected] towards real groundwater samples isolated in Qatar depends upon the physicochemical characteristics of each element.