共存氣體對氫氣滲透鈀膜之影響

Effect of Co-existing Gas on Hydrogen Permeation through Palladium Membrane

莊賀欽(He-Chin Chuang)

指導教授 ： 洪賑城

大同大學/工程學院/化學工程學系所/碩士(2012年)

摘要

本研究利用半批次裝置，探討共存氣體(包含氮氣、水、甲醇、水與甲醇)對於氫氣滲透鈀膜之影響。同時以純氫氣滲透鈀膜實驗監測鈀膜管活性退化之情形，並探討鈀膜管再生之方法。
採用下列純氫或混和氣中氫氣滲透鈀膜之數學模式：
"J=" "β" _"ref" " exp" {" " ("-" "E" _"a " )/"R" (" " "1" /"T" "-" "1" /"T" _"ref" " " )" " }{("P" _"H" )^"n" "-" (〖"P" _"R" "+P" 〗_"0" )^"n" }" "
其中J為氫氣滲透通量；〖〖T_ 為實驗溫度；T〗_ref 為參考溫度；β〗_ref為在參考溫度之滲透係數；E_a為活化能； PH為高壓端氫氣之分壓；PR為平衡時高壓端與低壓端氫氣分壓之差；P0為低壓端之氫氣分壓；n為指數。
利用純氫氣滲透實驗數據及上述模式可迴歸出模式中之參數。 實驗結果發現，實驗溫度越低，鈀膜管活性退化越明顯，而在663K及純氫氣狀況下過夜處理，鈀膜管之活性可恢復。
實驗結果亦證實氮氣、水蒸氣、甲醇或甲醇及水為共存氣體時， PR=0。當氮氣為共存氣體時，除了氫氣分壓降低所造成之氫氣通量下降外，還有額外之降低效應，且整體之活化能亦改變。含5%、10%及15%甲醇之混合氣之氫氣滲透係數分別為純氫氣之91%、87%及83%。在共存氣體為水與甲醇(莫耳比1:1)之狀況下，各個溫度之氫氣滲透係數都需向下修正才能使模式計算值正確估計實驗之結果。

關鍵字

氫氣滲透鈀膜之影響

並列摘要

The effect of co-existing gas, including nitrogen, water, methanol and mixture of methanol and water, on hydrogen permeation through palladium membrane has been studied in a semi-bath device. Pure hydrogen permeation experiment was conducted to monitor the activity of the palladium membrane, and regeneration of palladium membrane was also investigated.
The following mathematical model is adopted for hydrogen permeation through palladium membrane with or without co-existing gas:
"J=" "β" _"ref" " exp" {" " ("-" "E" _"a " )/"R" (" " "1" /"T" "-" "1" /"T" _"ref" " " )" " }{("P" _"H" )^"n" "-" (〖"P" _"R" "+P" 〗_"0" )^"n" }" "
where J is hydrogen permeation flux; T is temperature; Tref is reference temperature; βref is permeance at Tref ; Ea is activation energy; PH and P0 are hydrogen partial pressures in retentate and permeate, respectively, PR is the difference of hydrogen partial pressure between retentate and permeate at equilibrium; and n is exponent.
The parameters in the mathematical model can be obtained from nonlinear data regression. Experimental results show that the deactivation of palladium membrane increases with decreasing temperature. However, the activity can be recovered by treating the membrane tube with pure hydrogen at 633K overnight.
Experimental results also demonstrate that PR is zero when nitrogen, water, or methanol co-exists .When nitrogen co-exists, besides the decrease in hydrogen partial pressure, hydrogen permeance decreases and the activation energy changes significantly.When methanol co-exists, the hydrogen permeance of gas mixtures with 5, 10 and 15% methanol is only 91, 87 and 83% of that of pure hydrogen, respectively. When water and methanol (molar ratio 1:1) co-exist, the permeance has to be reduced so that the model calculations can agree well with the experimental data.

並列關鍵字

Hydrogen Permeation through Palladium Membrane

參考文獻

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