多種觸媒應用於節能式乙醇重組器產氫特性之研究

Hydrogen production from energy saving ethanol reformer with various catalysts

邱韋丞(Wei-Chen Chiu)

指導教授 ： 洪榮芳

崑山科技大學/工程學院/機械工程研究所/碩士(2008年)

摘要

本研究乃自行設計一套重組產氫系統，針對生質燃料-乙醇進行重組，目的在於探討多項參數對於重組產氫特性的影響。
實施方法為搭配不同金屬觸媒(Fe、Co、Ni、Pt、Pd、Rh、Ru)被覆於Al2O3上，配合不同氧碳莫爾數比、S/C比及乙醇流率；以部分氧化法及氧化蒸汽重組法重組產氫，並利用反應後重組氣體之廢熱搭配節能方式（熱絕緣及熱回收），探討其重組特性並與原系統比較。
經實驗研究結果可知，使用貴重金屬為較低溫度即可產生重組反應。使用適當的觸媒並配合較佳的節能方式，可以有效產出富氫氣體。熱回收方式搭配使用Rh觸媒，在O2/EtOH比為0.75時，可以得到最佳H2+CO濃度，約為46.15%；Ru次之約為44.41%。並由實驗得知，採用熱回收與熱絕緣兩種節能方式皆可改善乙醇的轉化效率、氫氣與一氧化碳的產出濃度及重組熱效率。其中並以Ru觸媒對熱效率改善率最為明顯，在O2/EtOH比0.5時，熱絕緣方式的熱效率約可提升19.38%，熱回收方式則約可提升39.43%；節能方式配合氧化蒸汽反應，使用Ru觸媒搭配熱回收系統、O2/EtOH比0.625、S/C比為1.0時，可對氫氣的產出獲得較佳的改善。
本系統之節能方式對系統重組確實有一定的效果，因此可利用較廉價之觸媒搭配利用節能方式，使其提升重組效率，來減少觸媒成本，但必須防止溫度過高而產生反效果，甚或造成觸媒燒結等傷害。

關鍵字

乙醇 ； 重組器 ； 節能 ； 產氫 ； 觸媒

並列摘要

This study investigated the reforming of bio-fuel, i.e., ethanol, for hydrogen production on energy saving ethanol reformer with various catalysts.
Various kinds of metal catalysts (Fe、Co、Ni、Pt、Pd、Rh、Ru) with washcoat of Al2O3 were used. The parameters investigated were O2/EtOH (Oxygen/Ethanol molar ratio), ethanol supply rate, S/C (Water/Ethanol ratio). Hydrogen production by Partial Oxidation Reforming (POX) and Oxidative Steam Reforming (OSR) were applied. The energy saving methods of heat insulation and heat recycling on the reforming performance were compared.
The experimental results showed that the noble metal had the favorable reaction at low temperature. The higher hydrogen rich gas concentration was obtained by suitable catalyst and energy saving schemes. The best (H2+CO) concentration of 46.15% was at O2/EtOH of 0.75 by rhodium (Rh) and next was by ruthenium (Ru) about 44.41% with heat recycling. Moreover, the ethanol conversion, concentration of hydrogen and carbon monoxide and the thermal efficiency of reforming were improved by the methods of heat insulation and heat recycling. The thermal efficiency had the most obvious improvement by using Ru catalyst with heat insulation and heat recycling methods. The improvement in thermal efficiency was 19.38% by heat insulation and 39.43% by heat recycling respectively at O2/EtOH of 0.5.With Oxidative Steam Reforming (OSR) and energy saving methods of heat recycling,Under O2/EtOH of 0.625 and S/C of 1.0 improved by hydrogen production.
That is, the reforming performance of the reformer system could be improved by energy saving schemes. Therefore, the enhancement in reforming could be obtained by the combination of low-price catalyst and the energy saving system. However, the reverse reaction of H2 which caused the defect in reforming, or even the damage of the catalyst due to the high temperature should be avoided.

並列關鍵字

Ethanol Reformer ； Energy saving schemes ； Hydrogen production ； Catalyst

參考文獻

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