比較氨及甲烷於含銅鋁雙金屬活性碳觸媒還原反應去除一氧化氮之研究

Influence of Reduction Agents on the Activity of Reduction of NO by Cu/Al Activated Carbon Catalyst

本研究探討以不同比例的硫酸鋁與硝酸銅製備而成的活性碳觸媒，以氨及甲烷作為還原劑對於還原降解一氧化氮(500 ppmv)效率之影響。實驗結果發現以氨為還原劑時，當硫酸鋁與硝酸銅的比例為1:9與3:7時，溫度為350℃以上，一氧化氮的去除率可達95%以上。若活性碳觸媒不含鋁金屬，以甲烷為還原劑，氮氧化物還原降解率於400℃時只有75%左右，顯示硫酸鋁金屬於氮氧化物還原降解中極為重要。以鋁／銅(1:9)活性碳觸媒進行一氧化氮之還原反應，若以甲烷為還原劑，去除一氧化氮的效率最高僅可達90%，以650ppmv氨作為還原劑，則有99%以上之還原效率。本研究中氮氧化物之去除率，受反應溫度高低之影響甚鉅。本研究中所製備之含鋁銅雙金屬活性碳觸媒以氨與甲烷作為還原劑時，皆能達到良好一氧化氮還原降解效果。

The purpose of this study focused on the influence of various reduction agents (NH3 and CH4) on the reduction efficiency by using Cu/Al activated carbon catalyst for NO reduction. The ammonia and methane were used as reduction agents in selective catalytic reduction. The effects of metals ratio in catalyst were investigated by discussing their reduction efficiency in reaction. It was found that the ratio of 1:9 ad 3:7 of Al to Cu in activated carbon could remove more than 95% NO at over 350℃ reduction reaction based on the ammonia test. On the other hand, the reduction efficiency was only 90% based on methane as the reduction agent. It was found that the rich in copper content in activated carbon catalyst enhanced the reduction efficiency and small aluminum in catalyst showed as a promoter in reduction. In this study, the highest reduction efficiency (more than 99%) can be achieved by using ammonia as reduction agent. But the 90% conversion was achieved by using the methane as reduction agent at the same condition. The reaction temperature also played an important role in this catalytic reduction system.