Adsorption desulfurization performance and adsorption-diffusion study of B2O3 modified Ag-CeOx/TiO2-SiO2

Meiqin Zheng; Hui Hu; Zhuoliang Ye; Qingming Huang; Xiaohui Chen

doi:10.1016/j.jhazmat.2018.09.037

Adsorption desulfurization performance and adsorption-diffusion study of B₂O₃ modified Ag-CeO_x/TiO₂-SiO₂

J Hazard Mater. 2019 Jan 15:362:424-435. doi: 10.1016/j.jhazmat.2018.09.037. Epub 2018 Sep 13.

Authors

Meiqin Zheng¹, Hui Hu², Zhuoliang Ye², Qingming Huang³, Xiaohui Chen⁴

Affiliations

¹ National Engineering Research Center of Chemical Fertilizer Catalyst, School of Chemical Engineering, Fuzhou University, Fuzhou, 350002, Fujian, P.R. China.
² School of Chemical Engineering, Fuzhou University, Fuzhou, 350116, Fujian, P.R. China.
³ Testing Centre, Fuzhou University, Fuzhou, 350116, Fujian, P.R. China.
⁴ National Engineering Research Center of Chemical Fertilizer Catalyst, School of Chemical Engineering, Fuzhou University, Fuzhou, 350002, Fujian, P.R. China. Electronic address: chenxhfzu@fzu.edu.cn.

PMID: 30261436
DOI: 10.1016/j.jhazmat.2018.09.037

Abstract

In this work, the adsorption desulfurization performance and adsorption diffusion study of B₂O₃ modified Ag-CeO_x/TiO₂-SiO₂ adsorbent were investigated. The adsorption desulfurization performance was studied by batch and fixed bed tests. The homogeneous surface diffusion model (HSDM) was employed to investigate the adsorption and diffusion behavior of 4,6-dimethyldibenzothiophene (4,6-DMDBT) in diesel. It was found that the addition of B₂O₃ promotes the dispersion of CeO_x species and then further facilitates the dispersion and oxidation of Ag species resulting in higher adsorption desulfurization activity. Ag species are in state of Ag, Ag₂O and Ag₂O₂, among which, Ag₂O and Ag₂O₂ are found to be the active centers. The kinetics of adsorption desulfurization of model diesel fuel was investigated to provide guiding significance for the prediction of breakthrough curves of fixed-bed adsorption columns. The batch kinetic experiment modeled by HSDM model indicates that surface diffusion controls the main rate. The surface diffusion coefficient D_s determined by batch adsorption experiments is independent of operation conditions, which can be used to directly predict the breakthrough behavior in fixed bed adsorption. The modified HSDM model is proposed to describe the breakthrough behavior. Results indicate that the breakthrough time is affected by bed height, flowrate and influent concentration.

Keywords: Adsorption desulfurization; B(2)O(3); Diffusion; HSDM.

Publication types

Research Support, Non-U.S. Gov't