NO在碳纳米管(CNTs),Rh/CNTs,Rh/Al_2O_3上的分解(英文)

甲烷在预还原的ＬａＣｏＯ３催化剂上分解生成碳纳米管（ＣＮＴｓ）。研究了稳态下ＮＯ在ＣＮＴｓ，Ｒｈ／ＣＮＴｓ，Ｒｈ／Ａ１２Ｏ３上的分解，温度区间为５７３Ｋ～９７３Ｋ，原料气为６０００ｐｐｍ的ＮＯ，Ｈｅ为平衡气。程序升温还原结果表明：（１）Ｒｈ的负载显著降低了ＣＮＴｓ的氢吸收量；（２）负载于ＣＮＴｓ上的Ｒｈ比负载于Ａ１２Ｏ３上的Ｒｈ更易还原。在５７３Ｋ时ＮＯ即能与预还原后的ＣＮＴｓ，Ｒｈ／ＣＮＴＳ，Ｒｈ／Ａｌ２Ｏ３中存储的氢反应；随着氢的消耗，反应活性逐渐降低，当储存的氢消耗完后，ＮＯ的直接催化反应发生。在８７３ Ｋ及以上，Ｒｈ／ＣＮＴｓ中的ＣＮＴｓ能彼ＮＯ分解产生的氧氧化为ＣＯ。在９７３Ｋ时，ＮＯ在ＣＮＴｓ上几乎能１００％分解，连续反应１５０ｍｉｎ后其反应活性不降低，且未观察到ＣＯ或ＣＯ２的生成。在９７３Ｋ时ＣＮＴｓ本身可作为ＮＯ分解的催化剂，这是一个非常有意义的结果。

NO DECOMPOSITION OVER CARBON NANOTUBES(CNTs), Rh/CNTs AND Rh/Al2O3

Carbon nanotubes (CNTs) were synthesized by means of CH4 decomposition over a pre-reduced LaCoO3 catalyst. The decomposition of NO has been Studied over CNTs, Rh/CNTs and Rh/|?-Al2O3. TPR results indicated that (i) the Rh loading lowered the H2 uptake of CNTs significantly, and (ii) the Rh in Rh/CNTs could be reduced more easily than that in Rh/Al2O3. NO was completely reduced at 573 K by the hydrogen stored in the three H2-reduced catalysts. After the complete consumption of stored hydrogen, direct catalytic decomposition of NO occurred. During NO decomposition at or above 873K, there was the oxidation of the CNTs in Rh/CNTs to CO.