Rhenium borides (Re3B and ReB2) mechanosynthesis and their use as a catalyst for H2 production from biomass pyrolysis

In this study, we report on Re3B and ReB2 mechanosynthesis. Re3B and ReB2 are used as catalysts in H-2 production by coconut shell pyrolysis from 500 to 800 degrees C and using 5, 10, and 20 wt % of catalyst. H-2, CH4, and CO production is monitored using gas chromatography with a thermal conductivity detector. Re3B shows the highest catalytic activity for H-2 production at 800 degrees C and 10 wt % of catalyst. Furthermore, Re3B reaches 77.4 % H-2 yield at optimal conditions, the highest value reported in the literature. Re3B and ReB2 were also characterized by temperature-programmed reduction (TPR) and Fourier transform infrared spectroscopy (FTIR). We propose a scheme for molecular hydrogen formation based on TPR and FTIR characterizations, thermodynamics analysis, and H-2 production.

Automated summary

This study reports on the mechanosynthesis of Re3B and ReB2 as catalysts for hydrogen production from coconut shell pyrolysis at temperatures ranging from 500 to 800 degrees C. Re3B exhibited the highest catalytic activity for hydrogen production at 800 degrees C and 10 wt % of catalyst, achieving a hydrogen yield of 77.4% under optimal conditions. The characterization of Re3B and ReB2 using TPR and FTIR allowed for the proposal of a scheme for molecular hydrogen formation based on thermodynamics analysis and hydrogen production data.