Development of Co–Nb–CeO2 Catalyst for Hydrogen Production from Waste-Derived Synthesis Gas Using Techno-Economic and Environmental Assessment

Abstract

A comparative study to obtain a cost-competitive catalyst was performed to produce hydrogen via the high temperature water gas shift (WGS) reaction using synthesis gas (syngas) derived from waste. First, several selected active metals on Nb–CeO2 support and preparation methods were applied to prepare highly active and stable catalysts under severe reaction conditions. Various characterization methods were employed to understand the correlation between catalytic activity and physicochemical properties of the prepared catalysts. Among the Me–Nb–CeO2 (Me = Co, Cu, Fe, and Zn) catalysts, Co–Nb–CeO2 showed the highest activity at a high gas hourly space velocity of 315,282 mL·g–1·h–1 (temperature = 500 °C, XCO ≈ 84%). This was attributed to the high Brunauer–Emmett–Teller surface area and oxygen storage capacity of the Co–Nb–CeO2 catalyst. In addition, to investigate the effect of preparation method, various methods, including coprecipitation, incipient wetness impregnation, sol–gel, and hydrothermal methods, were applied for the synthesis of the Co–Nb–CeO2 catalyst. The Co–Nb–CeO2 catalyst prepared using the coprecipitation method exhibited high activity without significant deactivation for 60 h. This was attributed to the high oxygen storage capacity and intimate interaction between Co and the Nb–CeO2 support. Finally, techno-economic analysis and environmental impact assessment were performed for the Co–Nb–CeO2 catalysts, prepared by different preparation methods to identify the most promising catalyst for the production of hydrogen using the syngas derived from waste. By comparison with a commercial catalyst, it was shown that Co–Nb–CeO2 synthesized using coprecipitation is a promising, cost-effective, and eco-friendly catalyst with high activity.