Adsorption Properties and Mechanism of U(Ⅵ) onto Oxidized Graphitic Carbon Nitride Nanomaterials

作者：Liu, Jin Xiang; Chen, Zi Geng; Xie, Shui Bo; Liu, Ying Jiu; Yu, Kun

来源：Fine Chemicals, 2019, 36(7): 1446-1452 and 1458.

DOI：10.13550/j.jxhg.20180855

• Adsorption equilibria
• Adsorption performance
• Adsorption properties
• Adsorption temperature
• G-C3N4
• Graphitic carbon nitrides
• Pseudo second order kinetics
• Water treatment technologies

Oxidized graphitic carbon nitride (OCN) nanomaterials were successfully synthesized by a acid etching and oxidation method.The adsorption-desorption performance of OCN nanomaterials for U(Ⅵ) was investigated.The effects of pH of solution, temperature, OCN dosage,contacting time and initial concentration of U(Ⅵ) were investigated by static batch experiments, and the adsorption mechanism was discussed.The experiments indicated that OCN exhibited superior adsorption performance to U(Ⅵ). Under the conditions of pH 5, adsorption temperature 30℃, initial concentration of U(Ⅵ) 10 mg/L, and OCN dosage 200 mg/L, the adsorption efficiency of OCN to U(Ⅵ) reached 98.9%, which was improved by about 42.82% compared with the unmodified graphite nitride carbon (g-C3N4), and the adsorption equilibrium was reached at 10 min. The adsorption process was greatly affected by the pH of solution and less affected by other factors such as temperature. The adsorption process was fitted well the pseudo-second-order kinetic equation and Langmuir model, and the adsorption process of OCN to U(Ⅵ) was spontaneous endothermic process. The results of adsorption desorption experiments revealed that OCN had good reusability.