本研究開發一組純化器,針對甲醇重組器所產出的富氫氣體進行純化,降低一氧化碳的濃度,避免毒化質子交換模燃料電池。目前所實施的方法為水氣轉移反應(Water Gas Shifting , 簡稱WGS)及優先氧化反應(Preferential Oxidation, 簡稱PROX),儘可能將降低富氫氣體之CO濃度。此研究方式將以不同種類的觸媒,利用混合氣(CO+N2),在不同的工作溫度之下,找出較佳的轉換效率。由實驗結果得知,WGS的反應在H2O/CO為3時,Pt/CeO2-ZnO2觸媒在觸媒工作溫度400℃,而CuO-ZnO觸媒在觸媒工作溫度300℃,有較佳的CO轉化效率,且在混合氣10%CO+90%N2下、與H2O/CO比為5時比較,在H2O/CO比為3時,轉化效率已趨近於穩定值。在水氣轉移配合一段優先氧化方面反應方面,在O2/CO比為4時,CO濃度可達到86ppm。
This project designed a reactor to remove the CO of the reformate gas produced by a methanol reformer to prevent the poison of the PEMFC. Water gas shift (WGS) and preferential oxidation (PROX) were adopted to remove CO in the hydrogen rich gas. CO and N2 mixture was introduced into various kinds of catalysts under suitable operation temperature to get the best CO conversion efficiency. The results showed that the best CO conversion efficiency was obtained at the temperature of 400oC with Pt/CeO2-ZnO2 catalyst, and the temperature of 300oC with CuO-ZnO catalyst under H2O/CO=3 by WGS reaction. Moreover, it was also found that the results of H2O/CO=5 and 3 were almost the same under 10%CO+90%N2 input mixture. Further, the best output CO concentration of 86 ppm was obtained under O2/CO=4 by the combination of WGS and one-stage PROX reaction.