In Situ Preparation and Regeneration Behaviors of Zinc Oxide/Red Clay Desulfurization Sorbents

Abstract

High-temperature gas desulfurization is an efficient and environmentally friendly process for syngas cleanup. The present study investigated the in situ preparation of a zinc oxide/red clay desulfurization sorbent and its desulfurization–regeneration behavior in O2/N2 atmospheres. The effects of regeneration temperature, space velocity, and O2 concentration on the regeneration behaviors of ZnO/red clay sorbents were also investigated. The surface and structural properties of the sorbents before and after regeneration were characterized by thermogravimetric–differential scanning calorimetry, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, elemental mapping, and N2 adsorption–desorption analyses. According to the results, the highest regeneration rate was achieved under the conditions of 6 vol % O2 and a space velocity of 3000 h–1 at 650 °C. After four cycles of desulfurization–regeneration experiments, the breakthrough time of the regenerated sorbents reduced by 18.7% and...