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

Publication date: 28 April 2017
Source:Separation and Purification Technology, Volume 177
Author(s): Ying Xiong, Yang Song, Qiang Tong, Peng Zhang, Yuejiao Wang, Zhenning Lou, Feng Zhang, Weijun Shan
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.

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