Novel ZnO-NiO-graphene-based sorbents for removal of hydrogen sulfide at intermediate temperature

• Published in: Fuel (Guildford) Vol. 314; p. 122724
• Main Authors: Sánchez-Hervás, J.M., Maroño, M., Fernández-Martínez, R., Ortiz, I., Ortiz, R., Gómez-Mancebo, M.B.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.04.2022; Elsevier BV
• Subjects: Adsorption; Catalysts; Corrosion products; Desulfurization; Fixed beds; Gas cleaning; Gas streams; Graphene; Hydrogen; Hydrogen sulfide; Nickel oxides; Refineries; Sorbent; Sorbents; Sulfur; Syngas; Synthesis gas; Zinc; Zinc oxide; ZnO-NiO-rGO composite; Gas cleaning; Desulfurization; Sorbent; Graphene; ZnO-NiO-rGO composite; Syngas
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2021.122724

•New family of reduced graphene Zn-Ni-rGO sorbents synthesized.•Prepared by non-expensive and easily replicable methods.•Studied for the first time for H2S reactive adsorption for syngas to biofuels.•Lab-scale performance studied for fixed bed desulfurization in syngas processing.•Better capacity at intermediate temperature than the commercial counterparts. When syngas is upgraded to bio-refinery products, hydrogen sulfide removal is necessary to prevent corrosion of equipment and avoid poisoning of sulfur sensitive catalysts. Technologies relying on sorbents working in the 300–500 °C temperature range are desirable for better process integration. In this work, a new family of reduced graphene ZnO-NiO sorbents, Zn-Ni-rGO, were synthesized by non-expensive and easily replicable scalable methods and studied for the first time for hydrogen sulfide reactive adsorption. Preparation was based on the Hummers & the improved Tour methods followed by addition of Zn(NO3), Ni(NO3), hydrothermal reduction and annealing. As obtained as well as post-reaction rGO-NiO-ZnO sorbents were characterized by XRF, XRD and N2 adsorption at −196 °C. The performance of the sorbents for fixed bed desulfurization was determined at lab-scale (P = 10 bar, T = 400 °C, GHSV = 3500 h−1) on a gas stream containing 9000 ppmv of H2S/N2. The sorbents showed better hydrogen sulfide removal capacity than the commercial one studied for comparison, what makes them a potential candidate for gas cleaning in the syngas-related sectors.