Precise control of heat-treatment conditions to improve the catalytic performance of V2O5/TiO2 for H2S removal

Jae Hwan Yang; Hyun Ji Lee; Hyun Soo Lee; Sang-Chae Jeon; Young-Soo Han

doi:10.1016/j.jhazmat.2021.125974

Precise control of heat-treatment conditions to improve the catalytic performance of V₂O₅/TiO₂ for H₂S removal

J Hazard Mater. 2021 Aug 15:416:125974. doi: 10.1016/j.jhazmat.2021.125974. Epub 2021 Apr 29.

Authors

Jae Hwan Yang¹, Hyun Ji Lee¹, Hyun Soo Lee¹, Sang-Chae Jeon², Young-Soo Han¹

Affiliations

¹ Department of Environmental Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, South Korea; Department of Environmental & IT Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, South Korea.
² School of Materials Science and Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongsangnam-do 51140, South Korea; Department of Materials Convergence and System Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongsangnam-do 51140, South Korea. Electronic address: scjeon@changwon.ac.kr.

PMID: 34492883
DOI: 10.1016/j.jhazmat.2021.125974

Abstract

The purpose of this study is to investigate the influences of atmospheric gas and temperature while preparing V₂O₅/TiO₂ catalysts to find a suitable heat-treatment method to improve catalytic performance during the process of H₂S removal. The catalysts prepared by wet-impregnation were heat-treated at different temperatures (400 or 600 ℃) under various atmospheres (Air, N₂, or H₂). The catalytic tests demonstrated that the catalyst heat-treated at 400 ℃ under N₂ atmosphere (N-400) possessed excellent catalytic activities regarding H₂S conversion (96.4%) and sulfur yield (89.1%). The characterization results revealed that the mild reducing condition employed for N-400 led to the formation of partially reduced V₂O₅ crystals and a strong V-Ti interaction owing to the anatase TiO₂ phase, resulting in the high oxygen vacancies on the catalyst surface. However, severe reducing conditions (H₂ or N₂ with 600 ℃) or the higher temperature (600 ℃) induced highly reduced V₂O_5-x or rutile TiO₂ related to a weak V-Ti interaction, respectively, which facilitated lower oxygen vacancies. This study is the first to demonstrate the significance of a precisely controlled heat-treatment to enhance catalytic performance for H₂S removal.

Keywords: Atmospheric gas; H(2)S removal; Heat-treatment; Oxygen vacancies; Temperature; V(2)O(5)/TiO(2) catalysts.