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Highlights • Corn straw was gasified and reformed with steam in a closed-loop reactor. • 10% Ni loadings on γ-A1 2 O 3 catalyst was synthesized and tested. • Reforming temperature, steam/biomass ratio, catalyst/biomass ratio was studied. • Syngas quality was upgraded by both the decoking and steam reforming reactions. Abstract A closed-loop gasification and catalytic reforming apparatus was applied for producing syngas from corn straw with upgraded syngas quality. Four nickel based catalysts at 10% and that at 5–15% loadings on γ-A1 2 O 3 were synthesized and tested. Effects of reforming temperature (700–900 °C), steam to biomass ratio (S/B, 0.5–2.5), catalyst to biomass ratio (C/B, 0.2–0.6) on the syngas quality and the carbon conversion and gasification efficiency were investigated. Incorporation of reforming reaction with 10% Ni/γ-A1 2 O 3 catalyst leads to the highest CO content (50.2%) and lowest CO 2 content (7.5%) amongst the four tested catalysts and amongst the Ni/γ-A1 2 O 3 catalysts at different Ni loading. The syngas was upgraded by both the decoking reaction in the pyrolytic chamber and the steam reforming and water shift reactions in the reforming chamber. [ABSTRACT FROM AUTHOR]

Highlights • Integrated gasification and catalytic reforming process with gas loop was developed. • Effects of support type, reforming temperature, S/B ratio, and C/B ratio was studied. • Ni/γ-Al 2 O 3 catalyst was used to upgrade quality and mitigate GHG potential of syngas. • Recirculated syngas can remove cokes on the used catalyst surface. Abstract The syngas that is produced from waste biomass often has high levels of CH 4 and CO 2 , which are greenhouse gases. This investigation presents an integrated gasification and catalytic reforming process with a closed gas loop that can improve quality of syngas from corn straw and mitigate CH 4 and CO 2 emission. The effects of the support type, reforming temperature, steam-to-biomass (S/B) ratio, and catalyst-to-biomass ratio (C/B) ratio on gas yield and composition were experimentally examined with waste corn straw as the feedstock gasified at 850 °C in the proposed closed-loop apparatus. Reformation of syngas using Ni/γ-Al 2 O 3 at 850 °C, S/B = 1 and C/B = 0.5 yielded 1.16 m3/kg of syngas, which contained 48.5% H 2 , 33.9% CO, 12.2% CO 2 and 5.3% CH 4 , corresponding to 71.0% and 81.5% enhancements of the first two and −77.8% and −58.1% reductions of the last two components. [ABSTRACT FROM AUTHOR]

Highlights • Chemical looping gasification of biomass was tested by 60% Fe 2 O 3 oxygen carrier. • Syngas was produced from rice straw, corn stalk, peanut shell and wheat straw. • H 2 /CO of syngas from rice straw was maximized experimental design. • The OC can be applied to generate syngas from biomass with promising outcomes. Abstract Chemical looping gasification is a promising technology to convert biomass into syngas with low adverse effects by heat loss and production dilution. This study utilized 60% loading Fe 2 O 3 /Al 2 O 3 oxygen carrier (OC) for gasification tests on four biomass samples: rice straw, corn stalk, peanut shell and wheat straw under OC/biomass (OC/B) ratio of 1.0, steam/biomass (S/B) ratio of 2.8, reaction time of 20 min, and reaction temperature of 850 °C. All biomass samples yielded similar gasification performances: CO content 19.2–23.1%, H 2 content 36.5–41.1%, carbon conversion rate 72.3–82.2% and gas yield 0.78–1.04 L/g. The gasification performance using rice straw was optimized on maximum H 2 /CO ratio using three levels Box-Behnken experimental design: 899.6 °C, 20.3 min, OC/B = 1.02 and S/B = 2.89, leading to maximum H 2 /CO value of 2.20. Verification tests confirmed this prediction. The adopted Fe-based OC can be applied to generate syngas from the tested biomass with promising outcomes. [ABSTRACT FROM AUTHOR]