水蒸汽对新型纳米铁（锌）基改性HKUST-1/MCFs微介孔复合材料强化吸附CO2机理研究

It is generally accepted that a reduction of the CO2 from power plants that promote climate change is necessary globally. It is rise to new challenge of a sharp decrease in separation efficiency due to the competitive adsorption of water vapor in coal-fired flue gas for CO2 capturing over traditional sorbent. Thus, the study of the effect of steam on enhanced mechanism of CO2 adsorption over nanoscale iron (zinc)-modified HKUST-1/MCFs micro-mesoporous composites was proposed. On the theoretical level, the effects of surface chemical properties of the nanoscale iron (zinc)-modified HKUST-1/MCFs micro-mesoporous composites on the adsorption equilibrium, kinetics, and selectivity will be discussed. H2O partially or completely dissociated to form a surface containing OH by optimizing iron (zinc)-based particles size and chemical properties. The adsorption mechanism between active components and CO2 will be investigated to reveal the intrinsic reasons of adsorption CO2 in the steam atmosphere over the composites. Furthermore, to optimize the micro-mesoporous composites and reaction conditions.of adsorption CO2 required. Technically, it is investigated that the CO2 capture from flue gas by the synergy of nanoscale iron (zinc)-modified HKUST-1/MCFs micro-mesoporous composites at high humidity. The results of the project have important application value and scientific significance for solving the effective CO2 capture under water vapor conditions.

CO2高效捕获的研究对于解决温室效应问题具有重大意义。针对实际燃煤烟气中含有的水蒸汽竞争吸附导致传统吸附剂捕获CO2性能急剧下降的问题，本项目提出了水蒸汽对纳米铁（锌）基改性HKUST-1/MCFs微介孔复合材料强化吸附CO2机理研究。从理论层面上，研究和揭示纳米铁（锌）基改性HKUST-1/MCFs微介孔新型复合材料表面性质对CO2、H2O吸附相平衡、动力学和分离选择性的影响规律，优化调节铁（锌）离子尺寸和化学性质，促进表面吸附H2O的解离，进而揭示水蒸汽条件下吸附剂CO2吸附的内在原因；从技术层面上，通过改性微介孔材料的协同作用，研制出高湿度条件下具有更高CO2吸附容量的纳米铁（锌）基改性HKUST-1/MCFs微介孔复合材料，项目成果将为解决实际含水蒸汽条件下新型CO2高效捕获这一难题提供新的理论和技术基础。

CO2高效捕获的研究对于“双碳”目标的实现具有重要的意义。针对实际燃煤烟气中含有的水蒸汽导致传统吸附剂捕获CO2性能急剧下降的问题。因此在前期研究基础上，本项目选择HKUST-1为基础进行改性，分别制备了HKUST-1/MCFs复合材料，Zn-HKUST-1/MCFs复合材料和Fe-HKUST-1/MCFs复合材料，考察了其抗水性能以及CO2吸附容量，并结合XRD、N2吸脱附、XPS、TEM等表征，借助DFT手段探究了复合材料的CO2吸附机理。主要内容及结果包括：. 制备了HK/MCFs-x复合材料用于CO2吸附过程，发现随着压力的增加，CO2吸附量也随之增加，表明压力是吸附过程的主要驱动力；在动力学方面，随着温度的升高，CO2的传质速率越快。然而，由于热力学的限制，材料的吸附容量逐渐降低。吸附材料具有良好的抗水性能和CO2吸附循环使用性能。. 制备了Zn-HK/MCFs-x复合材料用于CO2吸附过程，发现Zn-HK/MCFs-1:7.5具有最大的CO2吸附容量比HKUST-1/MCFs提高了31.5%。当含水量wt%=5-6时，二者的CO2吸附量有明显地增加，此时Zn-HK/MCFs-1:7.5比单纯HKUST-1的CO2吸附量提高65%。同时制备了Fe-HKUST-1/MCFs复合材料用于CO2吸附过程，发现有水存在时，吸附材料具有更高的CO2吸附容量。. 通过DFT计算表明，Zn-HK/MCFs-x具有更高的CO2吸附能力，且与CO2分子之间存在更多的电子转移和交换，有利于提高其CO2吸附能力。项目成果将为解决实际含水蒸汽条件下新型CO2高效捕获这一难题提供新的理论和技术基础。