Research Center of Solar Power & Refrigeration, School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
Institute of Technical Thermodynamics, Karlsruhe Institute of Technology, 76131, Germany.
Chem Soc Rev. 2022 Aug 1;51(15):6574-6651. doi: 10.1039/d1cs00970b.
Significant progress has been made in direct air capture (DAC) in recent years. Evidence suggests that the large-scale deployment of DAC by adsorption would be technically feasible for gigatons of CO capture annually. However, great efforts in adsorption-based DAC technologies are still required. This review provides an exhaustive description of materials development, adsorbent shaping, characterization, adsorption mechanism simulation, process design, system integration, and techno-economic analysis of adsorption-based DAC over the past five years; and in terms of adsorbent development, affordable DAC adsorbents such as amine-containing porous materials with large CO adsorption capacities, fast kinetics, high selectivity, and long-term stability under ultra-low CO concentration and humid conditions. It is also critically important to develop efficient DAC adsorptive processes. Research and development in structured adsorbents that operate at low-temperature with excellent CO adsorption capacities and kinetics, novel gas-solid contactors with low heat and mass transfer resistances, and energy-efficient regeneration methods using heat, vacuum, and steam purge is needed to commercialize adsorption-based DAC. The synergy between DAC and carbon capture technologies for point sources can help in mitigating climate change effects in the long-term. Further investigations into DAC applications in the aviation, agriculture, energy, and chemical industries are required as well. This work benefits researchers concerned about global energy and environmental issues, and delivers perspective views for further deployment of negative-emission technologies.
近年来，直接空气捕集（DAC）取得了重大进展。有证据表明，通过吸附大规模部署 DAC 每年可实现捕获数十亿吨 CO2。然而，仍需要在基于吸附的 DAC 技术方面付出巨大努力。本综述全面描述了过去五年中基于吸附的 DAC 的材料开发、吸附剂成型、表征、吸附机制模拟、工艺设计、系统集成和技术经济分析；在吸附剂开发方面，需要开发经济实惠的 DAC 吸附剂，如具有大的 CO 吸附容量、快速动力学、高选择性和在超低 CO 浓度和潮湿条件下长期稳定性的含胺多孔材料。开发高效的 DAC 吸附工艺也至关重要。需要研究在低温下运行、具有优异 CO 吸附容量和动力学性能的结构吸附剂、具有低热和质量传递阻力的新型气固接触器，以及使用热、真空和蒸汽吹扫的节能再生方法，以实现基于吸附的 DAC 的商业化。DAC 与针对点源的碳捕获技术之间的协同作用有助于长期缓解气候变化的影响。还需要进一步研究 DAC 在航空、农业、能源和化工等行业的应用。这项工作有助于关注全球能源和环境问题的研究人员，并为进一步部署负排放技术提供了视角。
