Preparation of porous calcium carbonate biochar and its beryllium adsorption performance

Wastewater disposal from beryllium production has become a significant problem in the industry. Therefore, this paper designed porous calcium carbonate biochar (CC-LBC) using Na2CO3 and CaCl2 to modify the biochar innovatively, after which we understudied the Be(II) adsorption effect of CC-LBC at different concentrations. The results from Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), and other characterization analyses showed that when CC-LBC particles were immersed in the Be(II) waste liquid, several O elements accumulated because of its loose and porous structure, generating more beryllium precipitates on the surface of the adsorbent. According to kinetic data fitting, investigations also revealed that both physical and chemical reactions controlled CC-LBC/Be(II) adsorption process, indicating that the CC-LBC/Be(II) adsorption system is suitable for the intraparticle diffusion model. Furthermore, when the beryllium on activated carbon was desorbed by 10% NaOH, the desorption effect was above 80%, and the saturation adsorption capacity of CC-LBC for Be(II) was up to 55 mg/g. However, when the initial concentration of Be(II) was equal to 0.5–1 mg/L, the concentration of beryllium after treatment was lower than 10 μg/L, confirming that CC-LBC had a better selective adsorption performance for beryllium in the binary system.