The Synthesis and Characterization of Graphene Supported CeO2 and ZrO2 Adsorbents


Derekaya F., Sever E. E.

International Online Conferance On Engineering And Natural Sciences, Gümüşhane, Turkey, 5 - 07 July 2021, pp.1-2

  • Publication Type: Conference Paper / Summary Text
  • City: Gümüşhane
  • Country: Turkey
  • Page Numbers: pp.1-2

Abstract

Recently, heavy metal removal from wastewater works have gained importance. For this purpose, in this study, Graphene supported CeO2 and ZrO2 adsorbents were synthesized to be used in the removal of some impurities from wastewater. Three different preparation methods were used to synthesize CeO2-Gr, ZrO2-Gr, CeO2-ZrO2-Gr adsorbents: impregnation, hydrothermal and solvothermal methods. Adsorbents were characterized by using X-ray diffaction analysis, N2 physisorption measurements. The average crystal size of the catalysts were calculated using the XRD analysis data by using the Debye Scherrer equation. According to calculations, average crystal sizes range between 40.37Å and 164Å. The highest mean crystal size was observed in the CeO2-ZrO2-Gr adsorbent prepared by the impregnation method, the lowest in the CeO2-ZrO2 -Gr adsorbent prepared by the solvothermal method. When the methods were compared, it was observed that the highest average crystal size was in the adsorbents prepared by the impregnation method. By N2 physisorption analysis; surface areas, average pore diameters, pore volumes and adsorption-desorption isotherms were determined. The highest surface area was calculated as 203.8 m2 / g in ZrO2-Gr adsorbent prepared by hydrothermal method. Average pore diameters vary between 21.45 Å and 294.37 Å. The highest mean pore diameter was found in CeO2-ZrO2 –Gr adsorbent prepared by solvothermal method. Mesopore and micropore volume were determined from the desorbed nitrogen gas volume value at the last point of nitrogen adsorption/desorption isotherm. When we look at the values, it is seen that the macroporous volume results are higher in adsorbents. In the results we obtained, it was determined that the total volume of mesopores and micropore volumes in adsorbents synthesized by solvothermal method is higher than the catalysts prepared by other methods. It was observed that the total pore volumes of the adsorbents obtained by the hydrothermal method were higher than the total volumes of the catalysts prepared by other methods. When the isotherm curves were examined, it was observed that all the synthesized adsorbents fit Type 4.