|Abstract: ||本研究探討電極面積與緩衝溶液，對微生物燃料電池產電績效之影響。試驗所用之反應槽分為薄膜微生物燃料電池(PEM-MFC)和無膜微生物燃料電池(ML-MFC)等兩種。試驗期間燃料固定為250 mg COD/L之乙酸鈉溶液、水力停留時間為24小時與外部電阻為500 Ω。 首先，改變陰極電極面積由184 cm2增加至1290 cm2，結果發現，無論PEM-MFC或ML-MFC，最大功率密度會隨著陰極面積增加而增加。此外，當陰極面積大至某一程度時，內電阻會逐漸減少。 最後改變添加緩衝溶液濃度(mM)為0、25、50、75及100，結果發現，在PEM-MFC，陽極與陰極電極面積比為184：553時，最大功率密度(mW/m2)分別為3.69、11.72、12.99、13.14及11.44，內電阻由357 Ω減少至91 Ω，COD去除率(%)分別為49、58、75、51及26，庫倫效率由1.84 %增加至5.29 %。在ML-MFC，陽極與陰極電極面積比為1152：553時，最大功率密度(mW/m2)分別為1.66、6.42、11.55、13.16及10.93，內電阻由591 Ω減少至84 Ω，COD去除率(%)分別為98、95、88、91及99，庫倫效率由0.82 %增加至2.04 %。因此，藉由增加陰極電極面積與添加緩衝溶液，有助於降低反應槽之內電阻，進而提升產電效率。|
In this study, we investigate the effects of electrode area and phosphate buffer solution on the performance of microbial fuel cell (MFC). Two types of cell, Proton exchange membrane-MFC (PEM-MFC) and membrane-less MFC (ML-MFC), were employed. The fuel to the cell was 250 mg/L sodium acetate, the hydraulic retention time was 24 hours, and the external resistance was 500 Ω. The cathode area under test covered from 184 cm2 to 1290 cm2. Results indicated that for both PEM-MFC and ML-MFC, the power density increased with the increase of cathode area. In general, internal resistance decreased with increasing cathode area. The buffer solution (mM) added to the anode during the series of test run covered 0, 25, 50, 75 and 100. Results indicated that for PEM-MFC, when the area ratio of anode to cathode was 184:553, the maximum power density (mW/m2) was 3.69, 11.72, 12.99, 13.14 and 11.44, and the COD removal efficiency (%) was 49, 58, 75, 51 and 26, respectively. In addition, the internal resistance decreased from 357 Ω to 91 Ω, and coulombic efficiency increased from 1.84 % to 5.29 %, as the addition of buffer solution increased from 0 mM to 100 mM. For ML-MFC, when the area ratio of anode to cathode was 1152:553, the maximum power density (mW/m2) was 1.66, 6.42, 11.55, 13.16 and 10.93, and COD removal efficiency (%) was 98, 95, 88, 91 and 99, respectively. Additionally, internal resistance decreased from 591 Ω to 84 Ω, and coulombic efficiency increased from 0.82 % to 2.04 % as the addition of buffer solution increased from 0 mM to 100 mM. This study suggested that the increase of cathode area and the addition of buffer solution can decrease internal resistance, thus bringing about the improvement of electricity production.