Glass-Based Processing of Mixed-Oxide Desulfurization Sorbents

Abstract

The favorable thermodynamics of the reaction between H2S and oxides of iron, nickel, and zinc make these materials suitable for the sorption of sulfur from coal-derived synthesis gas. As an alternative to traditional solid-state processing, the suitability for coal gas desulfurization of glass-ceramics based on transition metal oxides has been evaluated. Glass-ceramics based on NiAl2O4 and ZnFe2O4 have similar sorption properties and a high resistance to agglomeration, but the inexpensive raw materials and moderate processing temperature of the ZnFe2O4-based glass makes it more suitable for a commercial application. The overall performance is highly dependent on the particle size of the sorbent, but these materials can be formed with relatively high surface areas by using fiber-based processing. This material is a potential alternative to mixed oxide sorbents prepared by solid-state processing, as it offers comparable performance combined with the ability to process the glass by existing glass-processing techniques.