氢能为实现零碳排放的能源利用提供了重要解决方案。 然而,受制氢技术限制,现阶段我 国主要以化石燃料为原料通过气化或重整得到 CO,再通过水气变换制氢。 虽然使用化石燃料制氢 拥有80%的能量转换效率,但其制氢生命周期的平均CO2排放量近14 kg/kg(CO2 /H2),不利于实 现“双碳目标”。 因此,在化石燃料经水气变换制氢过程中,如何分离去除CO2是影响H2纯度和减 少能耗的关键步骤。 相比于常用的醇胺溶液法高能耗,CO2原位捕集强化水气变换制氢利用固体吸 附剂原位捕集产气中CO2,可实现一步制取高纯度H2且富集回收纯CO2。 因CO2的移除量和移除速 率直接决定水气变换反应的强化程度,关系到H2的产率和纯度,其运行稳定性与生产成本相关。 因 此,该工艺的高效运行依赖于高活性水气变换催化剂和CO2吸附剂。 为此,针对CO2原位捕集强化水 气变换制氢的原理及优势进行详述,总结了水气变换催化剂、MgO 基 CO2 吸附剂和双功能复合催化剂 在使用过程中存在的问题和相应的改进措施,阐述了 CO2 原位捕集强化水气变换制氢要实现工业化 需重点攻关的问题,并提出未来研究应综合考虑反应器选择与复合催化剂设计,通过工艺优化,实现 系统物质转化、能量利用和经济性能的最优耦合,揭示 CO2 原位捕集对制氢能耗降低的内在本质。

Hydrogen energy provides an important solution for realizing zero carbon emission energy utilization. However,due to the limitation of hydrogen production technology,China mainly employs fossil fuels as raw materials to produce hydrogen via water gas shift reaction. Although hydrogen production from fossil fuels has an energy conversion efficiency of 80%,its average CO2 emission in hydrogen production life cycle reaches nearly 14 kg/ kg(CO2 / H2 ), which is not conducive to realize the “carbon peaking and carbon neutrality goal” in China. Therefore,how to separate and remove CO2 is a key point to obtain high purity hydrogen and reduce energy consumption in the process of hydro- gen production from fossil fuels via water gas shift. Compared with the high energy consumption in the common etha- nolamine solution approach,the CO2 sorption enhanced water gas shift could remove CO2 in-situ by solid sorbents,and produce high-purity hydrogen and enrich pure CO2 in one-step. In this process,the CO2 removal amount and rate directly determine the extent of water gas shift reaction enhancement,which is related to the yield and purity of H2 . Mo- reover,its stability determines the hydrogen production cost. Therefore,the efficient operation of this process depends on the preparation of highly active water gas shift catalyst and CO2 sorbent. In this study,the principle and advantages of CO2 sorption enhanced water gas shift are firstly introduced. The authors summarize the problems and corresponding improvement approaches about the water gas shift catalyst,MgO based CO2 sorbent and dual function composite cata- lyst,and put forward the key problems that need to be tackled in order to realize the industrialization of CO2 sorption enhanced water gas shift. In the future research,the reactor selection and composite catalyst design should be compre- hensively considered,and the optimal coupling of material conversion,energy utilization and economic performance of the system should be realized through process optimization so as to reveal the inherent nature of CO2 in-situ cap- ture to reduce energy consumption in hydrogen production.