In this study, we introduced mesoporosity by post-synthesis modification of binder-containing zeolite 4A (Z4A) bodies using urea treatment, to synthesize hierarchical zeolite 4A (HZ4A) with tailored textural properties. Hierarchical zeolite 4A such as HZ4A-1−3, HZ4A-1−1, and HZ4A-3−1 were synthesized by varying the urea to zeolite weight ratio as 1:3, 1:1, and 3:1 respectively. The synthesized HZ4A displayed tunable physicochemical characteristics, where HZ4A-1−3 exhibited improved surface area (126 m² g⁻¹), enhanced mesopore volume (0.44 cm³ g⁻¹) and co-existence of both micro (ca. 0.4 nm) and mesopores (5.5 nm). HZ4A-1−3 also exhibited enhanced CO₂ adsorption performance even when exposed to moisture at 1 bar and 40 °C. Moreover, HZ4A-1−3 displayed excellent CO₂ adsorption stability over ten consecutive adsorption-desorption cycles. The presence of mesopores in HZ4A-1−3 facilitated rapid gas diffusion within the pores during both adsorption (29 s faster) and desorption (92 s faster), low water adsorption capacity (20 % lesser), mild desorption temperature (13 °C lesser) and low CO₂ heat of adsorption (14 % lesser) as compared to Z4A bodies, and hence achieved better CO₂ adsorption efficacy for HZ4A-1−3 with reasonable CO₂ regeneration energy. These results suggested the potential of hierarchical zeolite 4A (HZ4A) as a cost-effective sorbent for post-combustion CO₂ capture application.

在这项研究中，我们介绍了介孔性，方法是通过尿素处理后对含粘合剂的4A沸石（Z4A）体进行合成后的改性，以合成具有定制纹理特性的分层4A沸石（HZ4A）。通过将尿素与沸石的重量比分别改变为1：3、1：1和3：1来合成诸如HZ4A-1-3，HZ4A-1-1和HZ4A3-1的分级沸石4A。合成的HZ4A显示出可调节的理化特性，其中HZ4A-1-3表现出改善的表面积（126 m ²  g ^-1），增强的中孔体积（0.44 cm ³  g ^-1）和两种微孔的共存（约0.4 nm） ）和中孔（5.5 nm）。HZ4A-1-3也表现出增强的CO ₂即使在1 bar和40°C的湿气下也具有吸附性能。此外，HZ4A-1-3在十个连续的吸附-解吸循环中表现出出色的CO ₂吸附稳定性。HZ4A-1-3中孔的存在促进了气体在吸附（较快29 s）和脱附（较快92 s）期间在孔内的快速气体扩散，低吸水量（降低了20％），温和的解吸温度（13°C）与Z4A物体相比，CO ₂的吸附热更低（降低14％），因此，在具有合理的CO ₂再生能量的情况下，对HZ4A-1-3的CO ₂吸附效率更高。这些结果表明，分级沸石4A（HZ4A）作为燃烧后CO ₂的经济高效吸附剂的潜力 捕获应用程序。