A hydropyrolysis process comprises feeding both (i) hydrogen and (ii) a biomass-containing feedstock or a biomass-derived feedstock, to a hydropyrolysis reactor vessel. The process comprises producing a CO2-containing vapor stream and at least one liquid product. A CO2 product, separated from the CO2-containing vapor stream, is advantageously used for at least one inertization function of the hydropyrolysis process. Representative inertization functions include operation of solids transport equipment, blanketing of liquid containers, drying of biomass-containing feedstock or biomass-derived feedstock, conveying or separating solids, and combinations thereof. Importantly, CO2 products utilized for these inertization functions may be obtained predominantly, if not completely (depending on the nature of the feedstock), from renewable carbon in biomass.