Adsorptive Removal of Radioactive Cesium from Model Nuclear Wastewater over Hydroxyl-Functionalized Mxene Ti 3 C 2 T x

作者：Yujing Chi, Yuan Xu, Chenxiang Xu, Jiming Tian, Ying Li, Boxiang Gu, Haiyan Song, Han Zhang · 发表于：Industrial & Engineering Chemistry Research · 年份：2022 · DOI：10.1021/acs.iecr.2c01297 · 被引用次数：40 · 研究领域：MXene and MAX Phase Materials、Chemical Synthesis and Characterization、Head and Neck Surgical Oncology

Selective removal of 137 Cs from nuclear wastewater is still a challenge due to the issues of efficient adsorbent exploitation and high concentrations of competitive ions. In this study, two-dimensional-layered Mxene Ti 3 C 2 T x achieved the surface alkaline modification with KOH to be used as an efficient adsorbent for Cs + removal from model wastewater. Hydroxyl-modified Ti 3 C 2 T x obtained improved the delamination morphology and surface structure compared with the pristine Ti 3 C 2 T x . In addition, the F species in Ti 3 C 2 T x were efficiently removed and the hydroxyl groups were increased after modification. The adsorption efficiency of Cs + over the hydroxyl-modified Ti 3 C 2 T x was significantly enhanced, being attributed to the improvements in morphology, structure, and properties. 0.05 g of an optimal adsorbent achieved 90% removal of Cs + with 5 mg·L –1 initial concentration in 50 mL of model wastewater within 5 min at ambient temperature and neutral conditions. Hydroxyl-modified Ti 3 C 2 T x also exhibited high adsorption selectivity for Cs + in the presence of competitive metal ions such as K +, Na +, Mg 2+, and Ca 2+ . The mechanism study revealed that the ion exchange between [Ti–O] − H + /Cs + mainly contributed to Cs + adsorption, and the complexation between the oxygen-containing groups [Ti–O] in modified Ti 3 C 2 T x and Cs was also involved. The hydroxyl-modified Ti 3 C 2 T x was easy to regenerate and exhibited good recyclability for Cs + adsorption...