Chemical looping combustion (CLC) provides a sustainable production of energy while inherently capturing carbon dioxide using oxygen carriers (OCs). To efficiently operate the reactor of the CLC, a thermodynamic analysis of OC is essential. This study focuses on the complete thermodynamic analysis of CLC employing iron-based OCs. In the analysis, methane as a reduction gas and air as an oxidizer along with the fuel and air reactors operated at 900 °C. Six different methane-to-hematite molar ratios (M/H) and O₂-to-hematite molar ratio (O/H) on iron oxide redox reactions are evaluated. The redox degree, including reduction and oxidation degrees of OCs in the fuel and air reactors, is introduced to figure out their performance. The results reveal that M/H = 1/15 with O/H = 1 yields the highest CO₂ and H₂O yields. Under six O/H ratios with M/H = 1/12, the highest CO₂ and H₂O yields are achieved at O/H ≥ 0.18. These operation conditions are conducive to carbon capture. In most cases of reduction and oxidation reactions, Fe₃O₄ and Fe₂O₃ account for the largest shares of iron in the OCs, respectively. The results show that a decrease in oxygen input to the air reactor leads to more carbon formed in the system. An enthalpy balance indicates an overall exothermic reaction behavior. Introducing the redox degree suggests that the optimal operation conditions are at M/H = 1/12 and O/H = 0.18. This study has provided crucial information about the operation and reactivity of iron oxides with methane in the chemical looping combustion process.

化学循环燃烧 (CLC) 提供可持续的能源生产，同时使用氧载体 (OC) 固有地捕获二氧化碳。为了有效地运行 CLC 的反应器，OC 的热力学分析是必不可少的。本研究侧重于使用铁基 OC 对 CLC 进行完整的热力学分析。在分析中，甲烷作为还原气体，空气作为氧化剂以及燃料和空气反应器在 900 °C 下运行。对氧化铁氧化还原反应中六种不同的甲烷与赤铁矿摩尔比 (M/H) 和 O ₂与赤铁矿摩尔比 (O/H) 进行了评估。引入氧化还原度，包括燃料和空气反应器中有机碳的还原度和氧化度，以计算其性能。结果显示 M/H = 1/15 且 O/H = 1 产生最高的 CO ₂和 H ₂ O 产率。在 M/H = 1/12 的六个 O/H 比率下，最高的 CO ₂和 H ₂ O 产率在 O/H ≥ 0.18 时实现。这些操作条件有利于碳捕获。在大多数还原和氧化反应的情况下，Fe ₃ O ₄和 Fe ₂ O ₃分别占 OC 中铁的最大份额。结果表明，进入空气反应器的氧气输入减少会导致系统中形成更多的碳。焓平衡表示总体放热反应行为。引入氧化还原度表明最佳操作条件为 M/H = 1/12 和 O/H = 0.18。这项研究提供了关于氧化铁与甲烷在化学循环燃烧过程中的操作和反应性的重要信息。