Development of chromatographic process for the dynamic separation of 90Sr from high level liquid waste through breakthrough curve simulation and thermal analysis

Preparation of Two Novel Stable Silica-Based Adsorbents for Selective Separation of Sr from Concentrated Nitric Acid Solution

“…The calculated TOC leakage rates for (DtBuCH18C6 + Dodec)/SiAaC-g-ABSA and (DtBuCH18C6 + Dodec)/SiAaC-g-3-ABSA are less than 0.56 wt.% and 0.29 wt.%, respectively, indicating the good structural stability of the two adsorbents. In this study, the leakage rate of organic compounds is significantly reduced compared to that in previous work [17]. Figure 9 explains to us that this reduction in leakage rate is attributed to the intermolecular bonding between the -SO3H group introduced through grafting and DtBuCH18C6 through hydrogen bonding in our study.…”

“…The peaks at 469 cm −1 , 803 cm −1 , and 1096 cm −1 originate from the stretching vibration of the Si-O-Si [24]. After sulfonation modification of SiAaC using 3-ABSA and ABSA, the characteristic peak of S-O is observed at around 568 cm −1 [17]. Due to the partial overlap of the peak positions of S=O and Si-O, the S=O peak in the FTIR spectra of SiAaC-g-3-ABSA and Si-AaC-g-ABSA cannot be observed as an independent peak.…”

“…Figure 4 shows the adsorption selectivity of Sr by (DtBuCH18C6 + Dodec)/SiAaC-g-ABSA and (DtBuCH18C6 + Dodec)/SiAaC-g-3-ABSA in simulated high-level liquid waste. At a nitric acid concentration of 0.5 M, the sulfonic acid group promotes the coordination of the crown ether ring with Sr, resulting in the two adsorbents exhibiting good adsorption of Sr [17]. As the nitric acid concentration increases to 1 M, the coordination promotion of the sulfonic acid groups to the crown ether ring is inhibited, leading to a weakening of the adsorption of Sr by the two adsorbents.…”

“…To address the above issues, researchers have modified crown ethers to reduce their leakage in the aqueous phase. Several organic ligands, such as 1-dodecanol, tri-n-butyl phosphate, and dodecyl benzenesulfonic acid, are prone to form hydrogen bonds with crown ethers, and impregnating them into porous carriers can effectively reduce the leakage of crown ethers and thus improve the adsorption efficiency of Sr [15][16][17]. The modification of crown ethers' adsorbents using silica-based hybrid carriers could be applied to separate Sr in nitric acid environments.…”

“…But as with the existence of hydrophilic sulfonic acid group, the total organic carbon (TOC) in the liquid phase was still high due to the leakage of organic content from the adsorbent during the adsorption process, which needs to be further improved [17]. In this work, we investigated the static and dynamic adsorption properties of two novel stable silica-based adsorbents, (DtBuCH18C6 + Dodec)/SiAaC-g-ABSA and (DtBuCH18C6 + Dodec)/SiAaC-g-3-ABSA, by batch and column experiments on the two adsorbents on Sr.…”