## 4 Discussion  
Novel bifunctional metal-loaded polymer-silica composite (PSC) catalysts with different polymer and metal contents have been successfully synthesized. These materials were used in the HDO of FAc as a relevant reaction in the context of creating fuels and value-added chemicals from lignocellulosic-derived biomass, which proceed via a complex reaction network of acid and redox-catalyzed steps. A maximum yield of \(n\)-octane (the final product in the HDO of FAc) of 90% was obtained at 250 \({}^{\circ}\)C, 100 bar of H\({}_{2}\), and after 8 h of reaction time. The catalytic performance of the synthesized materials was significantly affected by both the metal and the polymer content, illustrating the tailorable catalytic properties of the metal-loaded PSC catalysts. Although more studies are required to shed light on the direct correlation between the catalytic properties and the reaction pathways, the obtained results illustrate the potential of metal-loaded PSC catalysts as tunable bifunctional catalyst for the complete deoxygenation of biomass-derived compounds.  
The following are available online at [[http://www.mdpi.com/2076-3417/9/12/2438/s1](http://www.mdpi.com/2076-3417/9/12/2438/s1)]([http://www.mdpi.com/2076-3417/9/12/2438/s1](http://www.mdpi.com/2076-3417/9/12/2438/s1)), Figure S1: Volume adsorbed (V\({}_{\text{ads}}\)) over relative pressure (p / p\({}_{0}\)) from N\({}_{2}\) sorption for (1)Pt(13)PSC recorded at \(-\)196 \({}^{\circ}\)C. Figure S2: Reactant concentration of the self-condensation products of acetone over time for the HDO of FAc carried out using (1)Pt(13)PSC as a catalyst and acetone as a solvent (T = 250 \({}^{\circ}\)C, pH\({}_{2}\) = 100 bar, m\({}_{\text{cataly}}\) = 0.25 g, 0.5 g FAc (24.5 mmol l\({}^{-1}\)) dissolved in 150 ml acetone, stirring speed = 1000 min\({}^{-1}\)). Figure S3: Product fractions obtained for the reusability studies of (1)Pt(13)PSC in the HDO of FAc (T = 250 \({}^{\circ}\)C, pH\({}_{2}\) = 100 bar, m\({}_{\text{cataly}}\):m\({}_{\text{FAc}}\) = 2:1, cF\({}_{\text{Ac}}\) = 24.5 mmol l\({}^{-1}\), solvent: cyclohexane, stirring speed = 1000 min\({}^{-1}\)). The catalyst was washed five times with 50 ml cyclohexane and subsequently dried for 5 h at 200 \({}^{\circ}\)C in an air atmosphere between the experiments. Table S1: Productivity (given as mmol octane produced per gram of noble metal and hour) and reaction conditions for the hydrodeoxygregation of 4-(2-furyl)-3-buten-2-one reported in literature and this work ((1)Ru(13)PSC)).  
**Author Contributions:** Data curation, R.R.; funding acquisition, D.K.; investigation, M.G. and R.R.; supervision, R.G. and D.K.; writing--original draft, M.G.; writing--review and editing, R.G. and D.K.  
Figure 6: Product fractions obtained for the HDO of FAc carried out using PSC catalysts containing 13 wt.% polymer and 1 wt.% metal content with different active noble metals (T = 250 \({}^{\circ}\)C, pH\({}_{2}\) = 100 bar, m\({}_{\text{cataly}}\) = 0.25 g, 0.5 g FAc (24.5 mmol l\({}^{-1}\)) dissolved in 150 ml cyclohexane, stirring speed = 1000 min\({}^{-1}\), X(FAc) > 99%).  
**Funding:** This research was funded by Czech Science Foundation, grant number P106/12/G015 and carried out at the UniCRE center (CZ.1.05/2.1.00/03.0071) whose infrastructure was supported by the European Regional Development Fund and the state budget of the Czech Republic.  
**Acknowledgments:** Acknowledgments go to FPS COST Action FP1306 (Valorization of Lignocellulosic Biomass Side Streams for Sustainable Production of Chemicals, Materials & Fuels using Low Environmental Impact Technologies).  
**Conflicts of Interest:** The authors declare no conflict of interest.