Characterization of Two-Step Tin-Based Redox System for Thermochemical Fuel Production from Solar-Driven CO2 and H2O Splitting Cycle

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• 作者：Ga毛l Lev锚que ; St茅phane Abanades ; Jean-Claude Jumas ; Josette Olivier-Fourcade
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2014
• 出版时间：April 9, 2014
• 年：2014
• 卷：53
• 期：14
• 页码：5668-5677
• 全文大小：824K
• 年卷期：v.53,no.14(April 9, 2014)
• ISSN：1520-5045

文摘

The solar thermochemical dissociation of H₂O and CO₂ for renewable fuel production from two-step SnO₂/SnO cycle is considered. This cycle is based on the solar production of SnO phase in a first endothermic step that is subsequently used for splitting CO₂ and H₂O in a second exothermic step. The reactivity of tin-based species was studied in order to elucidate the phenomena occurring during its heating and subsequent reoxidation in a H₂O or CO₂ atmosphere to produce H₂ or CO. Two main types of reactant were considered for comparing their reactivity: SnO nanopowder obtained via solar sublimation and condensation of commercial SnO powder, and Sn/SnO₂ nanopowder obtained via disproportionation of nanosized SnO. The reaction rate was quantified via thermogravimetry analysis and the reaction products were characterized using M枚ssbauer spectrometry and X-ray diffraction. The SnO and Sn/SnO₂ nanopowders are more reactive with H₂O than with CO₂ in the range 550鈥?50 掳C. SnO is also more reactive with oxidants than Sn/SnO₂. The disproportionation reaction starts significantly around 600 掳C, giving rise to a particular Sn^II phase that reacts faster with the oxidants but is more prone to passivation. A kinetic study yields an activation energy of 101 卤 10 kJ mol^鈥? and 53 卤 1 kJ mol^鈥? for the Sn/SnO₂ oxidation with CO₂ and H₂O, respectively.