Low temperature hydrogenation of levulinic acid into γ-valerolactone using hydrogen obtained by photoelectrochemical water splitting with optimized TiO2 nanostructures

• Published in: International journal of hydrogen energy Vol. 79; pp. 1044 - 1057
• Main Authors: Da Silva, Elianny, García, Adrián, Erans, María, Fernández-Domene, Ramón M., González-Alfaro, Vicenta, Solsona, Benjamin, Sánchez-Tovar, Rita
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 19.08.2024
• Subjects: Biofuel; Hydrogen; Photoelectrochemical water splitting; Ruthenium catalyst; TiO2 nanostructures; γ-valerolactone; Ruthenium catalyst; TiO2 nanostructures; γ-valerolactone; Biofuel; Photoelectrochemical water splitting; Hydrogen
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2024.07.088

A novel method for the production of a biofuel precursor and additive (γ-valerolactone) using in-situ generated hydrogen is reported. Firstly, a potential non-carbon fuel as hydrogen is generated from water through a photoelectrochemical approach employing a set of TiO2 nanostructures synthesized by hydrodynamic anodization. Secondly, this system was coupled with a reactor in a way that the hydrogen produced reacts with levulinic acid in the presence of a ruthenium catalyst to yield γ-valerolactone. The preparation procedure of TiO2 nanostructures was optimized and the influence of factors such as the rotation speed and the anodization media was investigated. The best photoelectrochemical performance corresponds to the nanostructure synthesized in lactic acid and using hydrodynamic conditions at a rotation speed of 1000 rpm. The optimal nanostructure was used as a photocatalyst for hydrogen production by water splitting, with the generated hydrogen being directly used for the transformation of levulinic acid into γ-valerolactone in the presence of a ruthenium catalyst supported on alumina. Using this optimal TiO2 and the ruthenium catalyst, a yield to γ-valerolactone of 93 % was obtained in only 5 h at 60 °C and atmospheric pressure. [Display omitted] •Optimization of photoelectrochemical water splitting with titania nanostructures.•Tandem process: photoelectrocatalysis and conventional heterogeneous catalysis.•In-situ generated hydrogen for biofuel production.•Clean fuels: hydrogen and γ-valerolactone.