Structure-activity relationships of Ni-Cu/Al2O3 catalysts for γ-valerolactone conversion to 2-methyltetrahydrofuran

Abstract

The activity of a series of impregnated Ni-Cu/Al2O3 catalysts was evaluated for the production of 2-methyltetrahydrofuran (MTHF) from γ-valerolactone using 2-butanol as solvent. These catalysts evidenced that their activities depend more on the metal phase nature then on the metal sites dispersion, achieving three times higher Normalized MTHF Productivity (NMP) the samples with the highest amounts of the Ni-Cu alloy. In addition, the activity of those high Ni-Cu alloy containing samples showed to be limited by their low surface acidity. The promotion of the alloy formation, acidity and metal-acid sites proximity was achieved by a co-precipitation method. This new catalyst, calcined and reduced at 450°C, allows a MTHF yield of 64% after 5h. The tested catalysts showed deactivation by carbon deposition which could be overcome by intermediate regeneration between runs. The best catalyst showed stable>54% MTHF yield for three consecutive runs.