• 文献标题:   Enhancement of adsorption capacity of reduced graphene oxide by sulfonic acid functionalization: Malachite green and Zn (II) uptake
  • 文献类型:   Article
  • 作  者:   SOGUT EG, KARATAS Y, GULCAN M, KILIC NC
  • 作者关键词:   adsorption, kinetic, malachite green dye, sulfonated graphene oxide, zinc ion
  • 出版物名称:   MATERIALS CHEMISTRY PHYSICS
  • ISSN:   0254-0584 EI 1879-3312
  • 通讯作者地址:   Van Yuzuncu Yil Univ
  • 被引频次:   0
  • DOI:   10.1016/j.matchemphys.2020.123662
  • 出版年:   2020

▎ 摘  要

Graphene oxide (GO) was synthesized according to the Hummers' method developed to remove some impurities such as malachite green dye and Zn (II) metal ion from aqueous solutions. However, due to the problem of dispersion in water, graphene oxide surface is generally functionalized or composites are prepared with different materials. For this reason, the produced graphene oxide is functionalized with sulfanilic acid to obtain reduced sulfonated graphene oxide (rGO-SO3H). For the characterization of materials, DR/UV-vis, Raman, FT-IR, SEM and SEM-EDX mapping techniques were used. Also, reduced graphene oxide (rGO) was evaluated as a comparative example in adsorption. Effect of parameters such as pH, initial concentration and temperature on the removal of metal ions and dye was studied. Equilibrium was achieved in 90 min. The highest percentage removal of rGO and rSGO was observed at pH = 7. Equilibrium isotherms are defined using nonlinear Langmuir, Freundlich, Dubinin - Radushkevich (D - R) and Sips adsorption isotherm equations. Maximum adsorption capacities were determined as 588.23 mg g 1 and 1111.11 mg g(-1) for malachite green, 166.66 mg g(-1) and 322.58 mg g(-1) for Zn (II), respectively for rGO and rGO-SO3H. Kinetic experimental results fit well with the pseudo-second order model for both dye and metal ion; coefficients of determination were close to 1. Thermodynamic studies showed that the adsorption was spontaneous and the adsorption processes were controlled by a physical mechanism.