PHYSICOCHEMICAL CHARACTERISTICS AND PROPERTIES OF NANO-MODIFIED COUPLED SMECTITE CATALYSTS WITH AG+/ZN2+

Authors

  • Shu-Lung Kuo Department of Technology Management, the Open University of Kaohsiung, Taiwan
  • Edward Ming-Yang Wu Department of Civil and Ecological Engineering, I-Shou University, Kaohsiung, Taiwan

DOI:

https://doi.org/10.53555/eijas.v5i2.118

Keywords:

Smectite, coupled catalysts, FT-IR, TEM analysis, thermal analysis

Abstract

This study used smectite clay as a carrier and exchanged Ag+ and Zn2+ onto the smectite via ion exchange. The coupled smectite-Ag/Zn catalysts at the nanolevel were formed after surface modification and high-temperature sintering. Various physicochemical experiments, such as Fourier-transform infrared spectroscopy (FT-IR) analysis, x-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) analysis, and thermal analysis, were conducted to further discuss the physicochemical properties of the smectite-Ag/Zn.

A function group analysis on the modified coupled smectite-Ag/Zn catalysts conducted via an FT-IR spectrum shows that the mineral structures of the catalysts remain intact after high-temperature sintering. In terms of the x-ray analysis, water tends to exist in the layer structure of the smectite, which is affected by humidity in the environment. After being modified by Ag and Zn, shrinkage occurs in layers of the smectite due to water loss. The spacing of layers is thereby narrowed. Moreover, a TEM observation of the coupled smectite-Ag/Zn catalysts after it was sintered at 350oC shows that the sizes of Ag+ and Zn+2 on the smectite-Ag/Zn are between 25-50 nm, respectively. This proves that Ag+ and Zn2+ do exist in the coupled smectite-Ag/Zn catalysts after they were exchanged, and that they are at the nanolevel. As for the thermal analysis, the findings show that significant melting occurs when the coupled smectite-Ag/Zn catalysts are sintered at 459oC, due to the oxidative pyrolysis of micromolecules or solvents.

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Published

2019-06-27

Issue

Vol. 5 No. 2 (2019): EPH - International Journal of Applied Science ( ISSN: 2208-2182 )

Section

Articles

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