Effects of O2, SO2, H2O and CO2 on As2O3 adsorption by γ-Al2O3 based on DFT analysis

Pengbo Hu; Qiyu Weng; Duanle Li; Tao Lv; Shujuan Wang; Yuqun Zhuo

doi:10.1016/j.jhazmat.2020.123866

Effects of O₂, SO₂, H₂O and CO₂ on As₂O₃ adsorption by γ-Al₂O₃ based on DFT analysis

J Hazard Mater. 2021 Feb 5:403:123866. doi: 10.1016/j.jhazmat.2020.123866. Epub 2020 Sep 2.

Authors

Pengbo Hu¹, Qiyu Weng¹, Duanle Li¹, Tao Lv¹, Shujuan Wang², Yuqun Zhuo³

Affiliations

¹ Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, PR China; Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, PR China.
² Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, PR China; Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, PR China; Engineering Research Center for Ecological Restoration and Carbon Fixation of Saline-Alkaline and Desert Land, Tsinghua University, Beijing 100084, PR China.
³ Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, PR China; Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, PR China; Engineering Research Center for Ecological Restoration and Carbon Fixation of Saline-Alkaline and Desert Land, Tsinghua University, Beijing 100084, PR China. Electronic address: zhuoyq@tsinghua.edu.cn.

PMID: 33264939
DOI: 10.1016/j.jhazmat.2020.123866

Abstract

In order to reveal the affecting mechanisms of flue gas on As₂O₃ adsorption by γ-Al₂O₃ and to enhance the adsorbing capacities of γ-Al₂O₃, the influences of flue gas constituents on As₂O₃ adsorption on γ-Al₂O₃(0 0 1) surface are investigated theoretically via density functional theory (DFT) in this study. The flue gas constituents selected include O₂, H₂O, SO₂ and CO₂. O₂ converts nearly all of the physisorption structures into chemisorption structures except one structure, in which the O₂ electron cloud does not interact with As₂O₃ molecule and therefore does not enhance the capture of As₂O₃. For the effects of H₂O, SO₂ and CO₂, they behave almost the same as those of O₂, but the physisorption structures vary from different constituents. The difference of stable adsorption structures of O₂, H₂O, SO₂ and CO₂ on the surface of γ-Al₂O₃ and their corresponding properties are the main reason for variance of positions and quantities of As₂O₃ physisorption structures. Results of this study could provide useful information for enhancing capture capacities of γ-Al₂O₃ under actual flue gas environments.

Keywords: Adsorption; As(2)O(3); DFT; Flue gas constituents; γ-Al(2)O(3).