Substrate effects on the recyclability of (CuCo)2(OH)2CO3 in catalytic transformation of levulinate esters to γ-valerolactone

γ-valerolactone (GVL) is a renewable and sustainable platform chemical derived from biomass, with broad applications in chemical synthesis and energy-related fields. Consequently, the development of efficient strategies for GVL production has attracted significant attentions. In this study, the hydrogenation of ethyl levulinate (EL) to GVL was investigated using copper-cobalt basic carbonate, (CoCu) 2 (OH) 2 CO 3 , as a catalyst. The influence of different substrates—including esters and acids such as EL, GVL, ethyl acetate (EA), and levulinate acid (LA)-on catalyst recyclability and performance was systematically evaluated. Among the substrates tested, EL exhibited the most favorable behavior, delivering a GVL yield of up to 96% in the second recycling cycle under optimized conditions. This superior performance is attributed to the synergistic interaction between the basic sites of the catalyst and the ability of metallic Cu to activate hydrogen, as well as the formation of larger metal particle clusters when EL is used as the substrate. Notably, the catalytic activity remained largely preserved even after the third recycling cycle. In contrast, when GVL was sued as the substrate, moderate yields were obtained, accompanied by the formation of surface coatings on the catalyst particles. Furthermore, both EA and LA induced varying degrees of catalyst etching, resulting in a drastic loss of activity, with negligible catalytic performance observed in the second cycle. These findings indicate that catalyst deactivation due to etching has a more pronounced impact on catalytic performance than structural changes associated with bimetallic cluster formation. This observation indirectly highlights the critical role of basic sites in maintaining catalytic activity during the hydrogenation process.