Continuous conversion of furfural to furfuryl alcohol by transfer hydrogenation catalyzed by copper deposited in a monolith reactor

A monolith reactor was fabricated by growing carbonaceous fibers in a copper tube (i.d. 2 mm) via copper-catalyzed acetylene polymerization. The fibers were oxidized with air to convert CC bonds to CO bonds and to improve hydrophilicity. –SO3H groups were anchored on the surface by amination. Cu species were introduced by deposition and subsequent reduction. The resultant Cu/CF-SO3H monolith reactor was used to continuously and selectively convert furfural to furfuryl alcohol. At 180 °C, the monolith catalytic reactor performed significantly and stably in a 500 h run, maintaining a 100% conversion with a >99% selectivity. Additionally, the monolith reactor also performed well in continuous transfer hydrogenation of other α,β-unsaturated compounds, including 5-hydroxymethyl-2-furaldehyde, benzaldehyde, and cyclohexanone.