Catalytic transfer hydrogenation (CTH) was concerned great attention because it does not need the use of high pressure H2. A series of Cu catalysts has been prepared for transfer hydrogenation of biomass derived furfural to furfuryl alcohol with formic acid. The prepared Cu based catalysts are thoroughly characterized by various technique such as XRD, TPR, TPD (NH3, CO2), TEM, FT‐IR, UV‐Vis, N2O pulse chemisorption and N2‐physorption method. For a comparison point of view, the activity tests of various copper based catalysts have also been carried out. Among all these, MgAl2O4 (MA) supported copper catalyst was found to be the best to give 90% selectivity of furfuryl alcohol from transfer hydrogenation of furfural. The excellent yield of furfuryl alcohol could be attributed to high density of surface active Cu species, proper surface acidic‐basic properties and metal support interaction. Moreover, Cu/MA catalyst was simply recovered and reused, which retained its original activity even after reaction without significant loss of original activity. Supporting its reusability and stability.

Activated red brick (ARB) clay material proved superb catalyst for selective conversion of 1,5-pentanediol (1,5-PDO) to tetrahydropyran (THP) and 1,6-hexanediol (1,6-HDO) to oxepane (OP) via dehydration under vapor phase conditions in a continuous flow reactor. As per scanning electron microscopy (SEM), SEM-EDX and X-ray fluorescence (XRF) techniques, ARB clay catalyst majorly possessed silica (quartz), and iron oxide (hematite) species, and synergistic texture contributed to the catalytic efficiency for prolonged time-on-stream (TOS). The combination of active Lewis and Bronsted acidic sites with weak to mild acidic nature in the ARB clay obviously facilitates the dehydration reaction with high selectivity, tetrahydropyran (82%) and oxepane (89%). ARB clay displayed superior catalytic properties in the dehydration of alcohols compared with activities of commercial silica and α-Fe 2 O 3 as catalysts. Commercial silica and α-Fe 2 O 3 catalysts possessing the Lewis acidic sites only did not facilitate synchronous dehydration mechanism.

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CO2-assisted dehydrogenation of benzyl alcohol to benzaldehyde over Cu nanoparticles dispersed on CeO2 was reported. Cu nanoparticles with an average size of ∼11.4 nm dispersed over CeO2 cubes were efficient in selective conversion of benzyl alcohol with a rate of formation of benzaldehyde of 250.99 μmol s–1 gcat –1. The high rate of reaction might be due to the miscibility of BOH in CO2, which led to enhanced diffusion of BOH reactant molecules toward active sites. The controlled surface acid–base sites were responsible for the activation of benzyl alcohol, and nearby Cu nanoparticles abstracted α-H of benzyl alcohol to form benzaldehyde. During a time on stream study, the Cu-CeO2 catalyst experienced a gradual deactivation in the presence of N2 as the carrier gas, while in the presence of CO2, it delivered constant activity for 24 h. In the presence of N2, in-situ generated hydrogen was responsible for the formation of much toluene via hydrogenolysis of benzyl alcohol. CO2 acted as a soft oxidant, which minimized the in-situ generated hydrogen via the reverse water gas shift reaction; as a result, the toluene formation and deposition of carbonaceous species were minimized.