Guo Youhong, Bolongaro Vittoria, Hatton T Alan
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Nano Lett. 2023 Nov 8;23(21):9697-9703. doi: 10.1021/acs.nanolett.3c02157. Epub 2023 Aug 9.
Carbon capture and sequestration are promising emissions mitigation technologies to counteract ongoing climate change. The aqueous amine scrubbing process is industrially mature but suffers from low energy efficiency and inferior stability. Solid sorbent-based carbon capture systems present a potentially advantageous alternative. However, practical implementation remains challenging due to limited CO uptake at dilute concentrations and difficulty in regeneration. Here, we develop sustainable carbon-capture hydrogels (SCCH) with an excellent CO uptake of 3.6 mmol g (400 ppm) at room temperature. The biomass gel network consists of konjac glucomannan and hydroxypropyl cellulose, facilitating hierarchically porous structures for active CO transport and capture. Precaptured moisture significantly enhances CO binding by forming water molecule-stabilized zwitterions to improve the amine utilization efficiency. The thermoresponsive SCCH exhibits a notable advantage of low regeneration temperature at 60 °C, enabling solar-powered regeneration and highlighting the potential for sustainable carbon capture to meet global decarbonization targets.
碳捕获与封存是应对当前气候变化的有前景的减排技术。水性胺洗涤工艺在工业上已成熟，但存在能源效率低和稳定性差的问题。基于固体吸附剂的碳捕获系统是一种潜在的有利替代方案。然而，由于在低浓度下的CO吸收有限以及再生困难，实际应用仍然具有挑战性。在此，我们开发了可持续碳捕获水凝胶（SCCH），在室温下对CO的优异吸收量为3.6 mmol g（400 ppm）。生物质凝胶网络由魔芋葡甘聚糖和羟丙基纤维素组成，有助于形成分级多孔结构以实现活性CO的传输和捕获。预先捕获的水分通过形成水分子稳定的两性离子显著增强CO结合，从而提高胺的利用效率。热响应性SCCH具有在60°C的低再生温度这一显著优势，能够实现太阳能驱动的再生，并突出了可持续碳捕获以实现全球脱碳目标的潜力。
