• 文献标题:   Efficient removal of chlorophenols from water with a magnetic reduced graphene oxide composite
  • 文献类型:   Article
  • 作  者:   YAN H, DU Q, YANG H, LI AM, CHENG RS
  • 作者关键词:   magnetic reduced graphene oxide composite, green preparation method, chlorophenol, adsorption mechanism
  • 出版物名称:   SCIENCE CHINACHEMISTRY
  • ISSN:   1674-7291 EI 1869-1870
  • 通讯作者地址:   Nanjing Univ
  • 被引频次:   12
  • DOI:   10.1007/s11426-015-5482-y
  • 出版年:   2016

▎ 摘  要

A magnetic reduced graphene oxide composite (MRGO) was successfully prepared by a simple and green method. MRGO was then used as an adsorbent and found to exhibit enhanced removal efficiency for various chlorophenols (CPs) from water compared with its precursors, graphene oxide (GO) and reduced graphene oxide. The CPs were o-chlorophenol, p-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. Among them, 2,4,6-trichlorophenol, which exhibited the lowest water solubility and highest molecular weight, most easily bound to MRGO. The preferential interactions between MRGO and CPs were hydrophobic interactions (pi-pi stacking and hydrophobic effect). This result was confirmed by the equilibrium adsorption behavior in which isotherms were all well described by Freudlich model, indicating heterogeneous and multilayer adsorption. Therefore, CP adsorption was more favored under neutral and acidic conditions, and the decreased removal efficiency of MRGO at higher pH levels was due to the improved hydrophilicity of CPs for deprotonation effect. Moreover, MRGO showed fast removal of each CP, achieving adsorption equilibrium within 10.0 min, presented efficient separation from water under an external magnetic field, and was easily regenerated using dilute NaOH aqueous solution after reaching saturated adsorption. Adsorption capacity of the regenerated MRGO had almost no loss until after five cycles. In summary, MRGO was an efficient adsorbent for the removal of various CPs and had considerable application potential in water treatment.