In this work, K₂CO₃-containing composite materials were synthesized based on a mesoporous zirconia aerogel prepared by an epoxide-assisted sol-gel method using supercritical drying in ethanol. The porous ZrO₂ was impregnated with an aqueous solution of potassium carbonate to obtain composite materials with K₂CO₃ weight content ranging from 9 to 29 wt%. All the composites were tested in the process of CO₂ absorption from the air with a relative humidity of 25% followed by thermal desorption at 200 °C. The samples after the CO₂ absorption step were characterized by Fourier transform infrared spectroscopy and X-ray diffraction methods. Among the materials studied, the composite sorbent containing 23 wt% K₂CO₃ demonstrated the highest dynamic CO₂ absorption capacity (4.6 wt%) in the temperature-swing absorption (TSA) cycles. The results indicate that a certain part of K₂CO₃ loaded into zirconia mesopores forms surface species which do not actively participate in the CO₂ absorption and desorption processes. For the composite K₂CO₃/ZrO₂ material with the optimal K₂CO₃ loading, CO₂ absorption capacity is higher compared to the values obtained for K₂CO₃/γ-Al₂O₃ composite sorbents studied under the same conditions. Taking into account that this material demonstrates stable CO₂ absorption capacity values in the consecutive TSA cycles and needs a relatively low temperature for regeneration, it should be considered for application in Direct Air Capture units.

在这项工作中，K ₂ CO ₃的含复合材料是基于通过使用乙醇超临界干燥的环氧化物辅助溶胶-凝胶法制备的中孔氧化锆气凝胶合成。用碳酸钾水溶液浸渍多孔ZrO ₂，以得到K ₂ CO _3的重量含量为9至29重量％的复合材料。所有复合材料均在相对湿度为25％的空气中进行CO ₂吸收，然后在200°C下热脱附的过程中进行测试。CO ₂之后的样品通过傅里叶变换红外光谱和X射线衍射方法对吸收步骤进行了表征。在研究的材料中，包含23 wt％K ₂ CO ₃的复合吸附剂在变温吸收（TSA）循环中显示出最高的动态CO ₂吸收能力（4.6 wt％）。结果表明，加载到氧化锆中孔中的K ₂ CO ₃的某些部分形成了表面物种，这些表面物种并不主动参与CO _2的吸收和解吸过程。对于具有最佳K ₂ CO ₃负载的复合K ₂ CO ₃ / ZrO ₂材料，CO₂相比所获得的K值的吸收能力是高₂ CO ₃ /γ-Al系_2个ö ₃在相同的条件下，研究复合吸附剂。考虑到该材料在连续的TSA循环中显示出稳定的CO ₂吸收能力值，并且需要相对较低的再生温度，因此应考虑将其用于直接空气捕获装置。