Preparation of Cu-MgO catalysts with different copper precursors and precipitating agents for the vapor-phase hydrogenation of furfural

This article presents the effects of three copper precursors and four precipitating agents on the catalytic performance of the corresponding co-precipitated Cu-MgO catalysts in the vapor-phase hydrogenation of furfural. The chemical and physical properties were analyzed by means of XRD, BET, SEM, and EDX techniques. The nitrate precursor provided the highest performance (conversion of ~89%). Whereas, the catalyst prepared with NaOH was the most efficient (furfuryl alcohol yield of >90%) during 240 min; the most durable conversion (~95%) was assured with Na_2-CO₃, and the highest selectivity to furfuryl alcohol (>97%) was achieved with K₂CO₃ as the precipitating agent. The least efficient catalyst (prepared with ammonium carbonate) led to 5-methylfurfural and 2,2-methylenebisfuran as the main byproducts. The major byproducts over the rest of the catalysts included tetrahydrofurfuryl alcohol, furfuryl ether, 1-pentanol, and 2-methylfuran. An increasing trend of furfuryl alcohol selectivity with time-on-stream was evident for all of the catalysts.