Landfill gas is a source of CH4 emission, also rich in
CO2 (up to 50 vol%). It can be upgraded to renewable
natural gas (RNG) by separating CO2 and impurities.
Alternatively, the CO2 contained in biogas can be
converted into CH4 via the Sabatier reaction, using
H2 generated by water electrolysis. For industrial
applications, it is beneficial to eliminate the energy intensive
CO2 separation step, converting biogas to RNG directly.
In this work, a series of 0.02-1 wt%
Ru/γ-Al2O3 catalysts were prepared by
wet impregnation and evaluated for a single-pass conversion of
CO2-CH4 mixtures. Through the catalytic
performance evaluation and characterization studies, the optimal Ru
loading was identified as 0.1-0.5 wt%. For these catalysts, CO2
conversion of 80-87% was achieved at 450 °C and 90,000 mL/(g h),
maintaining 95-99% selectivity to CH4 production. These
catalysts also showed excellent stability over 100 h on stream, while
maintaining 99-100% CH4 selectivity.