Improved Copper‐Zinc Based Catalysts for the Partial Dehydrogenation of Dicyclohexylmethanol

Cu/ZnO/ZrO 2 (CZZ) catalysts outperform conventional Cu/ZnO/Al 2 O3 (CZA) materials in methanol synthesis. Building on recent findings that CZA catalysts enable hydrogen release from the oxygen-containing LOHC compound dicyclohexylmethanol (H14BP) below 200◦C, this study investigates structure-activity correlations with CZZ catalysts in the partial dehydrogenation of H14-BP as a model reaction. CZZ materials were produced by continuous co-precipitation with subsequent batch suspension ageing. A ZrO2 content between 4 and 8 mol% increased the specific surface area and catalytic activity. Zn-rich materials with elevated aurichalcite [(Cu,Zn) 5 (OH) 6 (CO3 ) 2 ] content in the catalyst precursor achieved higher activity despite a reduced specific surface area. Ageing at 70◦C promoted aurichalcite formation and improved performance, whereas higher temperatures reduced the specific surface area. An initial pH value of 6.7 enhanced Zn uptake during ageing and increased dehydrogenation productivity by 45% compared to pH 7.1. High catalyst productivity correlated with aurichalcite contents up to 98% and small crystallite sizes. Overall, CZZ outperformed CZA catalysts in the partial dehydrogenation of H14-BP, with the aurichalcite phase playing a crucial role. ... mehrOur results demonstrate the potential of this material class for selective dehydrogenation reactions and enable targeted further development based on the correlation between material-specific properties and catalytic activity