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The steam gasification of biomass in the presence of calcium oxide offers a viable route for the dual purpose of hydrogen production and carbon dioxide (CO 2 ) capture. Although previous studies have dealt with experimental and intrinsic rate constants of carbonation and calcination of calcium looping cycles, the data has not been compared with thermodynamic or kinetic simulation. In this study, the thermodynamic and kinetic simulation of the CO 2 capture process using two calcium-based sorbents (i.e., Imasco dolomite and Cadomin limestone) have been studied using Aspen Plus software. The thermodynamic simulation was able to predict the overall trend of the CO 2 adsorption on dolomite and limestone. However, a kinetic model was also applied to achieve a more accurate analysis. The results show good agreement between the modeling and the experimental data obtained using a thermogravimetric analyzer (TGA). A shift in the reaction mechanism was observed with respect to temperature. The experimental data and kinetic model illustrated that the maximum conversion occurred at 650 °C.

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The possibility to obtain chemicals and/or fuels from renewable sources is an attractive option in order to develop an integrated biorefinery concept. Bioethanol can be a suitable starting material for the production of H 2 as fuel or syngas. Hydrogen is considered as a future energy vector that can meet the ever growing world energy demand in a clean and sustainable way. Moreover, it can be used as a green chemical for several other processes. In this work, the centralized production of pure hydrogen from bioethanol was investigated using the process simulation software AspenONE Engineering Suite. After designing the process and the implementation of kinetic expressions based on experimental data collected in our lab and derived from the literature, an economic evaluation and sensitivity analysis were carried out, assessing conventional economic indicators such as the net present value, internal rate of return, and pay-out period of the plant. In particular, three scenarios were studied by changing the fuel of the furnace that heats up the ethanol steam reformer, i.e., using methane, ethanol, or part of the produced hydrogen. Heat integration was also optimized for the best scenario. Sensitivity analysis was applied to investigate the economic performance of bioethanol steam reforming under different circumstances, changing feedstock cost, hydrogen selling price, taxes, and capital expenditure. The results highlight the advantages and drawbacks of the process on a large scale (mass flow rate of bioethanol 40 000 ton year −1 ) for pure hydrogen production from bioethanol. The higher return is achieved when using methane as auxiliary fuel. The process was strongly OPEX sensitive and very tightly correlated to the bioethanol cost and hydrogen selling price.