Sustainable hydrogenation of limonene to value-added products using Cu–Ni catalysts supported on KIT-5

Abstract

We synthesized a series of new catalysts of non-noble metals (Cu and Ni) supported on mesoporous silica KIT-5. The materials showed changes in their reduction profile due to the combination of the metals and differences in the particle sizes. The catalysts showed remarkable catalytic performance in hydrogenation of limonene at mild reaction conditions. The catalyst with pure Cu produced only the molecule p-Menth-1-ene, while the addition of Ni promotes the hydrogenation of this product leading to p-menthane, which is an attractive compound as a sustainable aviation fuel (SAF). Cost analysis highlighted the economic advantages of Cu-based catalysts, especially NiCu1:2/K5, offering cost savings in raw materials and increased selectivity toward economically valuable products. Moreover, Cu production was found to have a significantly lower carbon footprint than Ni production, emphasizing the environmental benefits of Cu-based catalysts. Therefore, these new materials underscore the economic and environmental benefits of bimetallic catalysts with an equimolar Cu:Ni ratio.