Cr(VI) removal via anion exchange on a silver-triazolate MOF.
Gram-scale synthesis of a silver-triazolato framework - {[Ag8(tz)6](NO3)2·6H2O}n(1-NO3; tz-=3,5-diphenyl-1,2,4-triazolate) - has been achieved, enabling the systematic investigation of its anion-exchange properties. Our experimental results show that the anion-exchange pattern of 1-NO3conforms to the so-called Hofmeister bias, which has been correlated to the hydrophobic nature of the MOF pores, and can be understood by considering the difference between the hydration energies of the exchanging anions. Furthermore, 1-NO3displays a fast, efficient, and reversible adsorption of HCrO4-(via anion-exchange) from Cr(VI)-containing aqueous solution (Qmax=37.0 Cr mg/g, 303K), rendering it a promising prototype of a recyclable MOF for Cr(VI) removal.
College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.
Li-Li
LL
Li
College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.
Xiao-Quan
XQ
Feng
College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.
Run-Ping
RP
Han
College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.
Shuang-Quan
SQ
Zang
College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China. Electronic address: yang@zzu.edu.cn.
Guang
G
Yang
Adsorption; Anion-exchange; Hexavalent chromium; Metal-organic framework; Removal