本研究以3-aminopropyltriethoxy-silane(APTS)改質之奈米碳管(carbon nanotubes, CNTs)為吸附材，模擬煙道除硫系統(flue gas desulfurization, FGD)後端的二氧化碳(CO2)進行吸附效率測試及評估實場應用之可行性。研究中測試出最佳材料改質條件、物理/化學性吸附量、等溫吸附及吸脫附測試等。由溫度(25-100°C)影響測試結果顯示，CNTs在50°C以下有較佳的吸附效能，適合低溫的煙道氣體吸附。在進流CO2濃度15%、50°C時，CNTs及CNT(APTS)之吸附量分別為21.5及83.3 mg/g，當氣流含水率達2.23%時吸附量可提升至108 mg/g(2.45 mmol/g)。在吸/脫附試程中，最佳高溫/低壓吸脫溫度及時間分別為130°C及1小時，CNT(APTS)經過50次反覆吸脫附後，吸附指標仍維持在80%以上。此外，與沸石及商用活性碳比較，兩者經APTS改質後吸附量分別為28.4和16.4 mg/g，而50次吸附指標則分別是46.4及17.6 %，效率皆較CNT(APTS)差。蒸氣再生測試中，CO2可於短時間內被脫附出，並於50次循環操作後，仍可濃縮70%以上。綜合研究成果顯示，CNT(APTS)吸附量較高、適合煙道氣溫度範圍(40-70°C)、脫附溫度低以及吸附指標高等優點，實場應用上具開發之潛力。 Carbon nanotubes (CNTs) were employed as sorbents which were 3-aminopropyltriethoxysilane(APTS) modified for CO2 capture from flue gas in post-flue gas desulfurization. The temperature tests reflected that adsorption capacity of CNT(APTS) decreased with the temperature indicating the exothermic nature of adsorption process. The experimental maximum adsorption capacity (qe) of CNTs and CNT(APTS) were 21.5 and 83.3 mg/g, respectively, at 50C with 15% of CO2 inlet. The qe increased with increasing water vapor in air stream, which raised to maximum (108 mg/g) with 2.23% of water vapor. The cyclic CO2 adsorption was conducted via combination thermal treatment and vacuum suction at 130C, 0.03 atm in 1 hour. The results show that the adsorption index (AI) at n=50 cycle for CNT(APTS) is 80%. Comparison of cyclic CO2 adsorption among APTS modified CNTs, granular activated carbon (GAC) and mordenite zeolite (MZ) indicating that the qe of CNTs, MZ and GAC are 83.3, 28.4 and 16.4 mg/g, respectively. The AI at n=50 cycle for CNT, MZ and GAC are 81.1, 46.4, 17.6%, respectively. With steam regeneration, CO2 can be concentrated from 15% to a product of 70% and desorption in shorter time. It reveals that CNTs is a possibly cost-effective CO2 sorbent in spite of their high unit cost at the present time. These results are favorable in their use as a sorbent for CO2 capture. This project provide useful information with respect to potential sorbents and the best operating conditions as design criteria for a full-scale CO2 sober in the field.