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The chemical looping gasification of residual biomasses—operated in fluidized beds composed of oxygen-carriers—may allow the production of biofuels from syngas. This biomass-to-fuel chain can contribute to mitigate climate change, avoiding the accumulation of greenhouse gases in our atmosphere. The ongoing European research project Horizon2020 CLARA (G.A. 817841) investigates wheat-straw-pellets (WSP) and raw-pine-forest-residue (RPR) pellets as feedstocks for chemical looping gasification. This work presents experimental results from devolatilizations of WSP and RPR, in bubbling beds made of three different oxygen-carriers or sand (inert reference), at 700, 800, 900 °C. Devolatilization is a key step of gasification, influencing syngas quality and quantity. Tests were performed at laboratory-scale, by a quartz reactor (fluidizing agent: N₂). For each pellet, collected data allowed the quantification of released gases (H₂, CO, CO₂, CH₄, hydrocarbons) and mass balances, to obtain gas yield (<i>η^av</i>), carbon conversion (<i>χ^av_C</i>), H₂/CO ratio (<i>λ^av</i>) and syngas composition. A simplified single-first order-reaction model was adopted to kinetically analyze experimental data. WSP performed as RPR; this is a good indication, considering that RPR is similar to commercial pellets. Temperature is the dominating parameter: at 900 °C, the highest quality and quantity of syngas was obtained (WSP: <i>η^av</i> = 0.035–0.042 mol_gas g_biomass⁻¹, <i>χ^av_C</i> = 73–83%, <i>λ^av</i> = 0.8–1.0); RPR: <i>η^av</i> = 0.036–0.041 mol_gas g_biomass⁻¹, <i>χ^av_C</i> = 67–71%, <i>λ^av</i> = 0.9–1.0), and oxygen-carries generally performed better than sand. The kinetic analysis suggested that the oxygen-carrier ilmenite ensured the fastest conversion of C and H atoms into gases, at tested conditions.