*3.1. Catalyst Preparation*

The ReOx-Rh/ZrO2 catalysts were prepared by successive impregnation as previously described [70]. ZrO2 was supplied by MEL Chemicals (XZO 632/18, 129 m<sup>2</sup> g<sup>−</sup>1, mesoporous, average pore diameter 9 nm). In a typical preparation, ZrO2 was first wet-impregnated with an aqueous solution of RhCl3 at room temperature for 7 h. After the evaporation of water, the resulting solid was dried at 100 ◦C overnight and calcinated under air at 500 ◦C for 3 h. The second impregnation was conducted with an aqueous solution of ammonium perrhenate (NH4ReO4), followed by a second calcination, a reduction step under H2 at 450 ◦C, and passivation under 1% *v*/*v* O2/N2.

### *3.2. Maritime Pine Extraction and Hydrolysis*
