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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。
Methane is decomposed to form carbon nanotubes (CNTs) on the prereduced LaCoO3 catalyst. The steady state decomposition of NO on CNTs, Rh / CNTs and Rh / A12O3 was investigated. The temperature range was 573K ~ 973K, the feed gas was 6000ppm NO, and He was the balance gas. The temperature-programmed reduction results show that: (1) Rh loading significantly reduces the hydrogen uptake of CNTs; (2) Rh supported on CNTs is more reducible than Rh supported on A12O3. At 573K, NO reacts with hydrogen stored in the prereduced CNTs, Rh / CNTS and Rh / Al 2 O 3. With the consumption of hydrogen, the reactivity decreases gradually. When the stored hydrogen is consumed, the direct catalytic reaction of NO occur. At 873 K and above, the CNTs in Rh / CNTs can be oxidized to CO by the NO decomposition. At 973K, NO was almost 100% decomposed on CNTs, and its reactivity did not decrease after continuous reaction for 150min. No CO or CO2 was observed. CNTs itself acts as a catalyst for NO decomposition at 973K, which is a very interesting result.