Study on CO2 Capture Characteristics and Kinetics of Modified Potassium-Based Adsorbents
Open Access
- 15 February 2020
- Vol. 13 (4), 877
- https://doi.org/10.3390/ma13040877
Abstract
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.This publication has 28 references indexed in Scilit:
- Analysis and Status of Post-Combustion Carbon Dioxide Capture TechnologiesEnvironmental Science & Technology, 2011
- CO2 capture on polyethylenimine-impregnated hydrophobic mesoporous silica: Experimental and kinetic modelingChemical Engineering Journal, 2011
- Mesoporous amine-modified SiO2 aerogel: a potential CO2 sorbentEnergy & Environmental Science, 2011
- Modeling adsorption of CO2 on amine-functionalized mesoporous silica. 2: Kinetics and breakthrough curvesChemical Engineering Journal, 2010
- Post combustion CO2 capture by carbon fibre monolithic adsorbentsProgress in Energy and Combustion Science, 2009
- Carbonation and Hydration Characteristics of Dry Potassium-Based Sorbents for CO2 CaptureEnergy & Fuels, 2009
- Continuous operation of the potassium-based dry sorbent CO2 capture process with two fluidized-bed reactorsInternational Journal of Greenhouse Gas Control, 2007
- Oxy-fuel combustion technology for coal-fired power generationProgress in Energy and Combustion Science, 2005
- Kinetics of the reactive absorption of carbon dioxide in high CO2-loaded, concentrated aqueous monoethanolamine solutionsChemical Engineering Science, 2003
- Removal of CO2Greenhouse Gas by Ammonia ScrubbingIndustrial & Engineering Chemistry Research, 1997