Adsorption-controlled preparation of anionic imprinted amino-functionalization chitosan for recognizing rhenium(VII)

• Published in: Separation and purification technology 2017-04, Vol.177, p.142-151
• Main Authors: Xiong, Ying, Song, Yang, Tong, Qiang, Zhang, Peng, Wang, Yuejiao, Lou, Zhenning, Zhang, Feng, Shan, Weijun
• Format: Article
• Language: English
• Subjects: Anionic imprinting; Chitosan; Molybdenum(VI); Rhenium(VII); Selective adsorption
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2016.12.028

Adsorption mechanism of Re(VII) on the I-EDA-CS may be attributed to the attraction between the amine groups and anionic complexes in the “cavities”. [Display omitted] •A novel anionic-imprinting amino-functional chitosan adsorbent (I-EDA-CS) was synthesized from waste crab shells.•ReO4− in the matching specific cavities reacted with amine groups by electrostatic attraction and chelation.•The removal efficiency of rhenium was rarely high. This study described the synthesis of the Mo(VI)-imprinted ethylenediamine (EDA) grafted chitosan (I-EDA-CS), which is a novel technique in combination with surface imprinting and polymer crosslinking. Results indicated that mass ratio of ammonium molybdate and chitosan as 1g:25g–3g:25g could be conducive to achieve higher adsorption capacity of Re(VII). The maximum adsorption capacity of Re(VII) was found to be 418.98mg·g−1 at 303K with an initial Re(VII) concentration of 500mg·L−1, while maximum adsorption of Re(VII) on the non-imprinted absorbent (N-EDA-CS) was just 83.92mg·g−1. The maximum selectivity coefficients of the I-EDA-CS for Re(VII)/Cu(II), Re(VII)/Zn(II), Re(VII)/Mn(II), Re(VII)/Fe(II) were 1.29, 1.9, 2.31, 1.81, respectively. It revealed that the Mo(VI)-imprinted adsorbent showed superior selectivity and affinity to Re(VII) in case of the existence of competition ions. The analysis results of FT-IR and XPS confirmed that the high adsorption selectivity of the I-EDA-CS attributed to the chelation and electrostatic attraction between the amine groups and Re(VII) anionic complexes in the “cavities”. Imprinted I-EDA-CS was successfully employed for the selective adsorption of Re(VII) from industrial wastewater.