Abstract:

Industrial by-product gas is an important resource for hydrogen production with a huge annual output in China. Due to the high impurity content, the recovery of hydrogen from by-product gas by conventional approach suffers from high energy penalty, high cost and low efficiency. Compared with the traditional method, the chemical looping hydrogen generation technology provides a promising way to convert industrial by-product gas into high-purity H₂ with shorter process. In this review, the technical advantages of chemical looping hydrogen generation technology from industrial by-product gas were discussed and the effects of different reducing gases were summarized systematically. During chemical looping hydrogen generation process, the reaction activity of H₂ was better than CO, while the reaction process of CH₄ was more complicated. Temperature had a more significant effect on the reaction characteristics of different gases, and the impurity gases, i.e., N₂ and CO₂, had a negative effect on the reduction process. For oxygen carriers, high activity and stability carriers were the focus of research, and the methods such as designing composite materials, doping heterovalent elements and loading ionic conductors were important ways to improve the performance. In general, the chemical looping hydrogen generation technology had achieved rapid progress, which can also provide a reference for other chemical looping technology.

Key words: industrial by-product gas, chemical looping hydrogen generation, oxygen carrier, hydrogen

摘要：

我国的工业副产气年产量巨大，是一种重要的制氢资源。由于其高杂质含量，回收其中的H₂需要采用复杂的工艺且成本较高，导致副产气的利用率低。相比传统方法，化学链制氢技术只需两步或三步即可制得H₂，为工业副产气转化为高纯H₂提供了一条很有前景的途径。本文针对工业副产气化学链制氢技术的研究进展，讨论了工业副产气化学链制氢工艺的技术优势，总结了不同还原气对化学链制氢过程的影响。在化学链制氢反应过程中，H₂的反应活性优于CO，而CH₄的反应过程复杂，反应温度对不同气体的反应特性影响较为显著，杂质气体N₂和CO₂会对制氢过程产生不利影响。针对载氧体，高活性和稳定性载氧体是研究的重点，设计复合型载氧体、掺杂异价元素和负载离子导体等方法是改善载氧体反应性能的重要途径。总的来讲，化学链制氢技术取得了较快的进展，也为其他化学链反应研究提供了借鉴。

关键词: 工业副产气, 化学链制氢, 载氧体, 氢气