在本文中,通过两步溶胶-凝胶法制备了二氧化硅气凝胶载体,并通过湿负载将活性组分K2CO3负载在载体上,得到改性钾基CO2吸附剂。由于反应条件对改性钾基吸附剂CO2捕集特性的影响,反应温度(50℃,60°C,70°C,80°C),水蒸气浓度(10%,15%,20%),CO2浓度(5%,10%,12.5%,15%),和总气体流量(400毫升/分钟,500mL/min,600mL/min)在自行设计的固定床反应器中进行了研究。同时,低温氮气吸附实验,扫描电子显微镜,采用X射线衍射仪对改性钾基吸附剂反应前后的微观特性进行了研究。结果表明,两步溶胶-凝胶法制备的二氧化硅气凝胶具有良好的微观结构,比表面积和比孔容分别高达838.9m2/g和0.85cm3/g,分别。负载在载体上的K2CO3的微观结构得到改善,提高了钾基吸附剂的CO2吸附性能。钾基吸附剂对CO2的吸附可以用Avrami分数阶动力学模型和修正的Avrami分数阶动力学模型更好地描述,这是一个复杂的多路径吸附过程,这与吸附位点和活性有关。最佳吸附温度,水蒸气浓度,CO2浓度,总气体体积为60°C,15%,12.5%,500毫升/分钟,分别。
In this paper, a silica
aerogel support was prepared by two-step sol-gel method, and the active component K2CO3 was supported on the support by wet loading to obtain a modified potassium-based CO2 adsorbent. As the influences of reaction conditions on the CO2 capture characteristics of modified potassium-based adsorbents, the reaction temperature (50 °C, 60 °C, 70 °C, 80 °C), water vapor concentration (10%, 15%, 20%), CO2 concentration (5%, 10%, 12.5%, 15%), and total gas flow rate (400 mL/min, 500 mL/min, 600 mL/min) were studied in a self-designed fixed-bed reactor. At the same time, the low-temperature nitrogen adsorption experiment, scanning electron microscope, and X-ray diffractometer were used to
study the microscopic characteristics of modified potassium-based adsorbents before and after the reaction. The results show that the silica
aerogel prepared by the two-step sol-gel method has an excellent microstructure, and its specific surface area and specific pore volume are as high as 838.9 m2/g and 0.85 cm3/g, respectively. The microstructure of K2CO3 loaded on the support is improved, which promotes the CO2 adsorption performance of potassium-based adsorbents. The adsorption of CO2 by potassium-based adsorbents can be better described by the Avrami fractional kinetic model and the modified Avrami fractional kinetic model, and it is a complex multi-path adsorption process, which is related to the adsorption site and activity. The optimal adsorption temperature, water vapor concentration, CO2 concentration, and total gas volume were 60 °C, 15%, 12.5%, and 500 mL/min, respectively.