CO2 capture performance of bifunctional activated bleaching earth （ABE） was investigated at atmospheric pressure. The sorbents were characterized by means of X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET）...CO2 capture performance of bifunctional activated bleaching earth （ABE） was investigated at atmospheric pressure. The sorbents were characterized by means of X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET）, Caron-Hydrogen-Nitrogen analysis （CHN）, Fourier transform infrared （FT-IR） and thermal gravimetric analysis （TGA）. The CO2 capacity was enhanced uia basic-modification and monoethanolamine （MEA） loading of the ABE sorbent to obtain a bifunctional surface property. Here, basic-modified calcined ABE with a 30 wt.% MEA loading （SAB-30） showed the highest CO2 capture capacity, but this was decreased with excess MEA loading （〉 30 wt.%）. At a 10% （V/V） initial CO2 concentration feed, the maximum capacity of SAB-30 increased from 2.71 mmol/g at 30~C {without adding moisture to the feed） to 3.3 mmol/g at 50℃ when adding 10% （V/V） moisture to the feed. Increasing the moisture concentration further reduced the maximum CO2 capacity due to the blocking effect of the excess moisture on the sorbent surface. However, SAB-30 could completely capture COg even in a 100% （V/V） initial CO2 concentration feed. A maximum CO2 capacity of 5.7 mmol/g for SAB-30 was achieved at 30℃. Varying the ratio of sorbent weight to total flow rate of the gas stream had no discernible effect on the equilibrium CO2 capture capacity. Avrami＇s equation and Toth＇s isotherm model provided a good fitting for the data and suggested the presence of more than one reaction pathway in the CO2 capture process and the heterogeneous adsorption surface of SAB-30. Thermodynamics studies revealed that CO2 capture on the bifunctional SAB-30 is feasible, spontaneous and exothermic in nature.展开更多
基金financially supported by the annual government statement of expenditurethe in-depth research cluster project of Chulalongkorn University (Energy cluster)+3 种基金the Thailand Research Fund (No. IRG5780001)Chulalongkorn UniversityFaculty of Science of Chulalongkorn UniversityRachadapisek Sompote Fund for Postdoctoral Fellowship, Chulalongkorn University
文摘CO2 capture performance of bifunctional activated bleaching earth （ABE） was investigated at atmospheric pressure. The sorbents were characterized by means of X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET）, Caron-Hydrogen-Nitrogen analysis （CHN）, Fourier transform infrared （FT-IR） and thermal gravimetric analysis （TGA）. The CO2 capacity was enhanced uia basic-modification and monoethanolamine （MEA） loading of the ABE sorbent to obtain a bifunctional surface property. Here, basic-modified calcined ABE with a 30 wt.% MEA loading （SAB-30） showed the highest CO2 capture capacity, but this was decreased with excess MEA loading （〉 30 wt.%）. At a 10% （V/V） initial CO2 concentration feed, the maximum capacity of SAB-30 increased from 2.71 mmol/g at 30~C {without adding moisture to the feed） to 3.3 mmol/g at 50℃ when adding 10% （V/V） moisture to the feed. Increasing the moisture concentration further reduced the maximum CO2 capacity due to the blocking effect of the excess moisture on the sorbent surface. However, SAB-30 could completely capture COg even in a 100% （V/V） initial CO2 concentration feed. A maximum CO2 capacity of 5.7 mmol/g for SAB-30 was achieved at 30℃. Varying the ratio of sorbent weight to total flow rate of the gas stream had no discernible effect on the equilibrium CO2 capture capacity. Avrami＇s equation and Toth＇s isotherm model provided a good fitting for the data and suggested the presence of more than one reaction pathway in the CO2 capture process and the heterogeneous adsorption surface of SAB-30. Thermodynamics studies revealed that CO2 capture on the bifunctional SAB-30 is feasible, spontaneous and exothermic in nature.
