Desulfurization of hot coal gas over high-surface-area LaMeOx/MCM-41 sorbents

We prepared LaMeOx/MCM-41 (Me = Co, Zn, Fe) sorbents of high specific surface area by means of sol–gel method. For comparison purposes, the unsupported composite metal oxides were also synthesized. Breakthrough and total sulfur capacity over LaFeO3/M41 were 3.24 and 3.70 g, respectively, significantly higher than the former (0.35 g) over unsupported LaFeO3. The materials were characterized using Brunauer, Emmett and Teller (BET), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (H2-TPR), temperature-programmed reduction and sulfidation (TPRS), and high-resolution transmission electron spectroscopy (HRTEM) techniques. Their ability for H2S removal was evaluated over a fixed-bed reactor, and the effects of reaction temperature, feed composition, and support on desulfurization were studied. The results of successive sulfidation/regeneration cycles (×10) revealed that the LaFeO3/M41 sorbent was stable enough for desulfurization of hot coal gas in chemical industry.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► LaMeOx/M41 (Me = Fe, Zn, Co) sorbents of high specific surface area was prepared by means of sol–gel method. ► Channel structure of MCM-41 promotes the diffusion of H2S molecules and enhances sulfidation rate of LaFeO3/M41. ► Structure of LaMeOx/M41 remains intact after sulfidation. ► MCM-41 as a support promotes attrition resistance and enhances the mechanical strength of sorbents.