Conversion of glycerol into renewable hydrocarbons employing platinum and iron catalysts supported on mixed zirconium and aluminum oxides

Currently, there is a growing demand for alternative energy sources. In this context, glycerol emerges as an important source of carbon because it is a byproduct of biodiesel production. It is possible to convert glycerol to several products with high value, highlighting products such as paraffin and light olefins. This work aims to evaluate mono and bimetallic Pt and Fe catalysts supported by zirconia and alumina for glycerol conversion to paraffin and light olefins. The presence of Fe in the catalysts provided higher selectivity for propylene, while the catalyst containing only Pt showed higher selectivity for ethane, and this distinct behavior may be related to the different reaction pathways followed by 1,2-propanediol. The Pt–Fe/ZrAl catalyst demonstrated the most promising results in the production of light olefins. Consequently, this catalyst was selected to evaluate the effect of the reaction conditions. The catalytic tests revealed that an increase in the reaction temperature from 300 to 350 °C, a reduction in the concentration of glycerol in the feed from 80 to 60 vol%, and employing an H₂ flow rate of 40 mL min⁻¹ favored the highest yield (30%) for paraffin and light olefins. The bimetallic catalyst (Pt–Fe/ZrAl) showed the lowest coke deposition rates, indicating a higher resistance to coke deposition.