本 研 究 利 用 半 批 次 測 試 裝 置,探討氮氣與水蒸氣對氫氣滲透鈀膜之影響。裝置內鈀膜管高壓端之壓力及滲透過鈀膜之氫氣總體積與時間之關係, 利用資料擷取系統(LabVIEW)紀錄並顯示於電腦中。本研究在一次實驗中可測得廣大壓力範圍(例如1 bar~10 bar)內氫氣滲透鈀膜之數據, 並利用滲透氫氣總體積對時間之關係計算氫氣滲透通量,最後由兩個數學模式(A 及B)來估算氫氣滲透通量與鈀膜兩邊氫氣分壓差之n 次方之關係。本研究利用最小平方法回歸實驗數據, 得到模式A 及B之最佳n 值。相關之R2 值皆大於0.99,代表模式A 或B 皆可準確回歸實驗數據, 而模式B 之準確度則略優於模式A。得到最佳n 值後,更可以推算出各種不同狀況之最佳滲透係數(β )值, 不同溫度之β 值亦符合Arrhenius Law。從氫氣與25%氮氣之混合氣實驗結果顯示, 氮氣之存在會降低鈀膜管之氫氣滲透通量。氫氣與水蒸氣混合氣實驗結果則顯示,水蒸氣之存在也會降低氫氣滲透通量,但其降低量與水蒸氣之含量無關。
In this study a semi-batch device has been used to study the effect of nitrogen and steam on hydrogen permeation through palladium membrane. The pressure of high pressure side of the palladium tube in the device and total volume of hydrogen permeated through the palladium tube and were acquired and recorded on the personal computer. Data of hydrogen permeation through palladium membrane in a wide range of pressure, 1 bar to 10 bar, can be obtained in a single experiment. The total volume of hydrogen permeated as function of time can be used to calculate the hydrogen permeation flux. Two mathematical models were used to estimate the relationship between the hydrogen permeation flux and pressure difference across the Pd membrane sides. The value of R-Squire are larger than 0.99, indicating both Model A and Model B can be used to regress the data accurately. However, the accuracy of Model B is slightly better than Model A. Least square approximation has been used in this study to obtain the optimal n value, the power for the pressure in the mathematical models. After the optimal n is obtained, the best value of permeance can be calculated. The experimental results of gas mixture of hydrogen and 25% nitrogen show that existence of nitrogen reduces the hydrogen permeation flux through the Pd tube. The experimental results of gas mixture of hydrogen and steam show that existence of steam reduces the hydrogen permeation flux, however, the reduction is in dependent of the content of steam.