甲烷部分氧化辅助的高温固体氧化物电解水制备氢与合成气的研究

It is highly in need to produce hydrogen gas for future fuel by developing high temperature solid oxide electrolysis technique, which has been currently limited with extensive electric energy input and low energy efficiency. Our proposal offers an advanced and effective way to co-produce hydrogen in a reduced cost and novel synthesis gas for Fischer-Tropsch reaction by synergistically combining partial oxidation of methane with solid oxide steam electrolysis. The preliminary thermodynamic analysis and preliminary cell testing have clearly demonstrated that the POM assisted SOEC can substantially reduce the electricity consumption. Further experimental and modeling evaluation on energy efficiency and electrochemical performance including open-circuit potential, current density and polarization resistance will be conducted for the POM assisted SOEC process. Fundamental studies including the anode composition, inlet gas composition such as CH4 content, electrolysis current and operating temperature effects on the anodic outlet gas composition will also be systematically investigated to achieve a better understanding of the POM promoted steam electrolysis process for steadily producing the synthesis gas with high production rate and selectivity. The proposal will serve as an important theoretical and experimental knowledge for accelerating the pace in the development of high temperature electrolysis for fuel production.

本项目结合发展高温电解水制氢技术的迫切需要，针对传统固体氧化物电解池（SOEC）在运行过程中效率较低、电能成本过高等问题，在甲烷辅助SOEC模式的基础上优化阳极反应，发展甲烷部分氧化反应（POM）辅助的SOEC模式在低成本制备氢气的同时生成高品位的合成气。本项目已从热力学角度初步揭示了POM辅助SOEC过程的热力学属性及其用于降低电解电能的优越性；还将继续研究POM辅助SOEC运行过程的能量演变、电化学性能，探究POM辅助SOEC模式对电解池电解效率及开路电压、电解电流、极化电阻等电化学性能的影响；探索阳极组成、反应物组成（包括CH4浓度、电解电流密度）、工作条件等对CH4氧化产物组分的影响规律。建立适用于POM辅助SOEC运行机制的固体氧化物电解池体系及工作条件，为推动高温电解水制氢技术的工业化应用提供理论和实验基础。

本项目针对传统固体氧化物电解制氢电耗高、效率低等问题， 在阳极侧引入甲烷，利用甲烷部分氧化反应与高温电解相耦合，高效低成本制备高品位合成气。项目利用热力学计算和实验等手段分别研究了传统和甲烷辅助电解模式的热力学属性、电化学性能及产物品质，建立了产物组成与进气组成、工作温度、电解电流之间的关系，研究表明甲烷辅助模式可将电解启动电压降至0，Ru、Ni浸渍后进一步提高甲烷辅助电解模式的性能，在850 oC、0.5 V条件下，产生的电解电流密度可达-1022 mAcm-2；通过调整进气组成、工作温度、电解电流等参数获得高CO和H2选择性、理想H2/CO比（~2）的高品位合成气，为费脱反应制备液态燃料直接提供原料。另外，发展了原位还原钙钛矿母体制备了催化剂@钙钛矿结构复合电极；研究其用于高温电解水制氢的电化学性能和稳定性，为推动高温电解水制氢技术的发展提供新方法和研究基础。