Combustion synthesis of porous ZnO monoliths for sulfur removal

Highly porous ZnO monoliths are prepared with potential applications as regenerable adsorbents for sulfur removal. ZnS/NaCl composite materials are first obtained by combustion synthesis from mixtures of zinc, sulfur and sodium chloride powders. After NaCl removal by lixiviation with water, they are converted into ZnO by thermal treatment under air. The crystalline structure, the microstructure and the porosity of the resulting monoliths are investigated by X-ray diffraction, scanning electron microscopy and Hg porosimetry. Their evolution after sulfidation–regeneration cycles is also considered.

► Simple and robust synthesis route for foam-like ZnO monoliths. ► Control of the monolith porosity thanks to the control of the combustion synthesis. ► Crystalline structure, microstructure and morphology characterization of the produced monoliths. ► Study of the monolith evolution after sulfidation–regeneration cycles. ► Applicability to sulfur removal.