Rapid magnetic solid‐phase extraction of Congo Red and Basic Red 2 from aqueous solution by ZIF‐8@CoFe 2 O 4 hybrid composites

• Published in: Journal of separation science 2016-09, Vol.39 (18), p.3647-3654
• Main Authors: Xu, Yan, Jin, Jingjie, Li, Xianliang, Han, Yide, Meng, Hao, Wu, Junbiao, Zhang, Xia
• Format: Article
• Language: English
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.201600630

Core–shell metal–organic framework materials have attracted considerable attention mainly due to their enhanced or new physicochemical properties compared with their single‐component counterparts. In this work, a core–shell heterostructure of CoFe 2 O 4 ‐Zeolitic Imidazolate Framework‐8 (ZIF‐8@CoFe 2 O 4 ) is successfully fabricated and used as an solid‐phase extraction adsorbent to efficiently extract Congo Red and Basic Red 2 dyes from contaminated aqueous solution. Vibrating sample magnetometry indicates that the saturated magnetization of ZIF‐8@CoFe 2 O 4 is 3.3 emu/g, which is large enough for magnetic separation. The obtained hybrid magnetic metal‐organic framework based material ZIF‐8@CoFe 2 O 4 can remove the investigated dyes very fast within 1 min of the contact time. The adsorbent ZIF‐8@CoFe 2 O 4 also shows a good reusability. After regeneration, the adsorbent can still exhibit high removal efficiency (∼97%) toward Congo Red for five cycles of desorption–adsorption. This work reveals the great potential of core–shell ZIF‐8@CoFe 2 O 4 sorbents for the fast separation and preconcentration of organic pollutants in aqueous solution before high‐performance liquid chromatography analysis.