Synthesis and characterization of magnetic carbonaceous materials from bamboo waste and investigation of their adsorption capability for cesium ions

In this work, we prepared a series of magnetic carbonaceous materials (CB200F, CB400F, CB600F, CB800F, and CB1000) from waste bamboo (RB) for the removal of cesium ions from water. Physicochemical properties such as pHpzc, specific surface area, and surface functional groups of the prepared adsorbents were evaluated and their cesium ion adsorption capability was also assessed. Consequently, the amount of cesium ions adsorbed was in the following order: CB1000F < RB < CB200F < CB800F < CB600F < CB400F. Additionally, the solid–liquid separation ability of the prepared adsorbent after adsorption was evaluated. The results showed that CB400F, CB600F, and CB800F could be easily separated from the sample solution with the action of the magnetic field under our experimental conditions. Moreover, the effect of parameters, including contact time, adsorption temperature, and pH, on the adsorption of cesium ions was studied. The adsorption of cesium ions was rapid, and the equilibrium was reached within 10 min for CB400F. The adsorption capacity decreased with increasing adsorption temperatures (45 °C < 25 °C < 7 °C), and the optimal pH for removing cesium ions was approximately 10. Finally, the selectivity of cesium ion adsorption using CB400F was assessed; anions including chloride ions, sulfate ions, and nitrate ions did not interfere with the adsorption of cesium ions by CB400F. These results provide valuable information regarding the adsorption of cesium ions using the CB400F from aqueous media. The suggested treatment in this study significantly contributes to the development of recycling technology for biomass waste and/or purification of wastewater containing cesium ions.