Multishell structured magnetic nanocomposites carrying a copolymer of pyrrole-thiophene for highly selective Au(III) recovery

作者：Zhu, Mingying; Zhang, Wei; Li, Yan; Gai, Ligang^*; Zhou, Jianhua; Ma, Wanyong

来源：Journal of Materials Chemistry A, 2016, 4(48): 19060-19069.

DOI：10.1039/c6ta06541d

• AQUEOUS-SOLUTION
• GOLD NANOPARTICLES
• METAL REMOVAL
• ION REMOVAL
• ADSORPTION
• SEPARATION
• XPS
• POLYMERIZATION
• POLYTHIOPHENE
• POLYSTYRENE

Magnetic nanocomposites with surface containing multiform heteroatoms have great potential for metalion recovery with a high throughput. In this paper, a copolymer of pyrrole-thiophene (cPPyTh) is formed upon the Fe3O4/SiO2 composite through chemical oxidation polymerization in aqueous medium, using a modified Fenton reagent (FeCl3 plus H2O2) as the oxidant. The resulting Fe3O4/SiO2/cPPyTh nanocomposites exhibit an enhanced acid resistance and an excellent adsorption performance for Au(III) recovery from multiionic aqueous solution. At room temperature, the adsorption capacity of Fe3O4/SiO2/cPPyTh toward Au(III) can dramatically increase to 559.7 mg g(-1) within 5 min, and finally reach an equilibrium adsorption capacity of 845.9 mg g(-1). Also, Fe3O4/SiO2/cPPyTh exhibits highly selective adsorption toward Au(III) versus interfering ions (Mg(II), Cu(II), Zn(II), As(V), Cd(II), and Pb(II)). After consecutive use for five times, the adsorption/recovery percentages of Au(III) from multiionic solution with Fe3O4/SiO2/cPPyTh retain 93.3%/92.3%, showing a good reusability of the adsorbent. Compared with that of Fe3O4/SiO2/polypyrrole, Fe3O4/SiO2/polythiophene, and many other adsorbents in recent reports, the superior adsorption performance of Fe3O4/SiO2/cPPyTh is attributed to the following facts: (i) the lowest unoccupied molecular orbital energy level with a relatively high upper band for cPPyTh is beneficial for Au(III) recovery upon Fe3O4/SiO2/cPPyTh through an adsorption-reduction mechanism; (ii) the synergistic effect offered by the lower oxidation potential of pyrrole compared with thiophene but the higher affinity of S to gold ion species compared with N.

• 出版日期2016
• 单位齐鲁工业大学