One-pot in situ construction of amido and hydroxyl co-modified layered double hydroxides for selective scandium adsorption

• Published in: New journal of chemistry Vol. 48; no. 8; pp. 3525 - 3532
• Main Authors: Huang, Siyu, Yuan, Cheng-Zong, Li, Jiang, Zhang, Lunliang, Zhao, Hongrui, Zhao, Wenkai, Zhang, Xiaomeng
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 19.02.2024
• Subjects: Adsorption; Calcium ions; Cobalt; Environmental protection; Hydroxides; Hydroxyl groups; Scandium; Selective adsorption; System effectiveness
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/D3NJ04232D

Selective recovery of scandium has always been a research challenge and hotspot. Adsorption recovery is an effective method for selective separation and has aroused wide interest due to its environmental protection, energy saving, and high-efficiency recovery of low-concentration Sc 3+ . In this work, 3-amidopropyltriethoxysilane (KH550) was successfully introduced onto layered double hydroxides (LDHs) using a one-pot in situ hydrothermal method. Compared to traditional methods, the novel one-step in situ strategy leads to more groups being loaded onto the LDHs. The material has a high adsorption capacity and selectivity for scandium. The optimized KH550-LDHs (4K-LDHs) prepared with the optimal modified volume of 4 mL showed a high saturated adsorption capacity of 22.73 mg g −1 and good scandium adsorption stability. This adsorbent not only selectively extracts Sc 3+ from mixed rare earth ion systems but also effectively recovers Sc 3+ from the Ca 2+ , Co 2+ , Mn 2+ , Zn 2+ and Al 3+ coexisting ion solutions. The synergy between amido and hydroxyl groups provides abundant active sites for selective adsorption. The research showed that the modified material was fitted with pseudo-second-order kinetics and the Langmuir model. This work provides a one-pot in situ construction strategy for preparing amido and hydroxyl co-modified layered double hydroxides for selective scandium adsorption.