摘要: | 全球暖化(Global Warming)為二十世紀後半以來全球關注的重要議題,降低溫室氣體(GHGs)之排放以減緩全球暖化已成全球關注的焦點。將CO2及CH4進行重組反應可同時減少兩種主要溫室氣體之排放,且主要產物為合成氣(Syngas)可做為燃料或經由費拖反應合成碳氫化合物,為具有潛力且值得發展之技術。本研究以介電質放電進行CO2/CH4重組,並以溶膠凝膠法製備具有鐵電性質之弛緩鐵電體(BaZr0.75Ti0.25O3 (BZT, εr = 149)或BaFe0.5Nb0.5O3 (BFN, εr = 2025))填入反應床輔助進行反應,結果顯示在CH4/CO2 =1、電壓為13.6 kV、頻率為20,000 Hz及總流率為40 mL/min之條件下,未添加鐵電材料、搭配BZT填充床及搭配BFN填充床的反應器所得之二氧化碳轉化率分別為51.0%、52.7%及57.0%,甲烷轉化率分別為64.6%、66.4%及72.0%,一氧化碳選擇性分別為54.0%、55.6%及59.2%,氫氣選擇性分別為59.1%、63.6%及65.5%。能量效率方面分別為3.19 mol/kWh、3.81 mol/kWh及3.83 mol/kWh,證明介電質放電和弛緩鐵電體之間存在協同效應。另一方面,在CH4/CO2 = 3、電壓為13.6 kV、頻率為20,000 Hz、總流率為40 mL/min之條件下且搭配BFN填充床進行重組時,能量效率達5.16 mol/kWh。;Global warming has been a big concern since 20th century and how to reduce the emissions of greenhouse gases (GHGs) into atmosphere has become an important issue. Carbon dioxide reforming of methane to generate syngas has the advantages of converting two major GHGs simultaneously and producing syngas to be utilized as fuel or as feedstock of Fischer-Tropsch process. This study is motivated to reform CH4 with CO2 via dielectric barrier discharge (DBD), and catalyst packed bed composed by BaZr0.75Ti0.25O3 (BZT, εr = 149) or BaFe0.5Nb0.5O3 (BFN, εr = 2025) prepared by sol-gel method. The results show that with the conditions of CH4/CO2 ratio of 1, applied voltage of 13.6 kV, frequency of 20,000 Hz and flow rate of 40 mL/min, the CO2 conversions achieved with DBD alone, BZT packed bed and BFN packed bed are 43.4%, 52.7% and 57.0%, respectively, in the meantime, methane conversion efficiencies are 64.6%, 66.4% and 72.0%, respectively. The energy efficiency achieved with plasma alone is 3.66 mol/kWh, and it increases to 3.81 mol/kWh and 3.83 mol/kWh, respectively, as BZT and BFN are used as the catalyst. The results proved the combination of DBD and relaxor ferroelectric induces synergistic effect and enhances DRM. Moreover, with feeding CH4/CO2 ratio of 3, applied voltage of 13.6 kV, frequency of 20,000 Hz, flow rate of 40 mL/min and with BFN packed bed reactor, energy efficiency reaches 5.16 mol/kWh which is significantly higher than that achieved with plasma alone. |