Abstract:

The emerging carbon-negative technologies like direct air capture (DAC) guarantee the carbon neutral and therefore receive growing attention. In this study, the characteristics of DAC are briefly analyzed. Amine-functionalized inorganic materials, polymers, metal hydroxides and carbonates are compared and reviewed in terms of trace carbon dioxide capture performance. And the relationship between adsorption capacity and kinetics with loading methods, and hierarchy texture of support are clarified. Finally, the challenges in this field and the suggestions from the point of energy-consuming and capture efficiency are put forward. Firstly, amine functionalized materials and solid base sorbent display better potential in practical application than physisorption materials. Secondly, integration and use of the existed deep removal processes as references could develop and optimize the process. At last, facing the sever environmental problems, the development of the new material and low energy-consuming regeneration method should be concentrated in the future.

Key words: carbon dioxide, direct air capture, physisorption, chemisorption

摘要：

直接空气捕集（DAC）等新兴负碳排放技术是实现“双碳”目标的托底技术保障，近年来受到广泛关注。本文简要分析了直接空气碳捕集技术的特性，归纳总结了胺功能化无机材料和聚合物、金属氢氧化物和碳酸盐、多孔材料等痕量二氧化碳捕集性能，初步分析了负载方式、载体结构等与吸附容量和动力学的关系。浅析了该领域发展面临的问题和机遇，从能耗和性能方面对捕集材料和技术的研发提出以下建议：相较于物理吸附材料，胺功能化材料和固体碱等化学吸附材料具有更好的应用前景；在工艺开发领域，可以借鉴其他低浓度气体深度脱除工艺的经验；另一方面，可以结合不同工艺优势，设计多种工艺耦合的流程；最后，在严峻的环境问题下，必须加快材料研发的步伐，未来的研究重点应集中在材料的设计和低能耗再生方式的开发上。

关键词: 二氧化碳, 直接空气捕集, 物理吸附, 化学吸附