Efficient Base Nickel-Catalyzed Hydrogenolysis of Furfural-Derived Tetrahydrofurfuryl Alcohol to 1,5-Pentanediol

Nickel(0) supported by strongly basic lanthanide hydroxides/oxyhydroxides (Ni-Ln, Ln = La, Pr, and Sm) is an efficient alternative noble metal-free catalyst for hydrogenolysis of tetrahydrofurfuryl alcohol (THFA) to 1,5-pentanediol (1,5-PeD) in organic solvents (e.g., isopropanol). The catalytic performance of Ni-Ln was studied both in batch and continuous modes. The highest yield of 1,5-PeD was 88% in a batch system and 73% in a flow system using 40Ni-La reduced. Interestingly, 40Ni-La reduced was not only selective (≥84%) but also stable in a long-term continuous run (386 h). It is proposed that a metal support interface (Ni-Ln) is responsible for cleaving the C–O bond of THFA via two initial steps: deprotonation of THFA and activation of hydrogen. Additionally, transfer hydrogenolysis took place in the presence of H2 in secondary alcohols, resulting in higher yields of 1,5-PeD under batch conditions. However, addition of H2 had almost no influence on catalyst selectivity to 1,5-PeD under flow conditions.