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研究了ＣｕＹ，Ｃｕ－ＺＳＭ－５分子筛制备条件对ＮＯ直接分解活性的影响．结果表明，在不同酸碱度下交换的ＣｕＹ分子筛，在ｐＨ＝９时活性较好，而Ｃｕ－ＺＳＭ－５型在ｐＨ＝７时较好．随交换度提高，Ｃｕ－ＺＳＭ－５活性上升，而ＣｕＹ交换度达４５％后活性趋于平稳：用ＤＴＡ，ＴＰＤ，ＸＰＳ及ＩＲ等技术，对活性中心进行了研究，表明钢是以水合离子形式与分子筛中Ｎａ＋进行交换．Ｃｕ－ＺＳＭ－５的活性位单一，ＣｕＹ上则有两种ＮＯ吸附位．经４００℃焙烧后，铜优先占据Ｙ的β笼，此即活性位．未经焙烧的样品中铜主要以Ｃｕ２＋存在．４００℃抽空处理产生Ｃｕ＋．讨论了ＮＯ在含铜样品表面的反应过程．
The effects of preparation conditions of CuY and Cu-ZSM-5 molecular sieves on the direct decomposition activity of NO were studied. The results show that the CuY zeolites exchanged at different pH values show good activity at pH = 9, while Cu-ZSM-5 is better at pH = 7. The activity of Cu-ZSM-5 increased with the degree of exchange increased, while the activity of Cu-ZSM-5 increased after the degree of exchange was 45%. The active sites were studied by DTA, TPD, XPS and IR techniques. The form is exchanged with Na + in the molecular sieve. Cu-ZSM-5 activity of a single, CuY there are two NO adsorption sites. After calcination at 400 ℃, copper preferentially occupies the β cage of Y, which is the active site. Copper is mainly present as Cu2 + in the uncalcined sample. The evacuation treatment at 400 ° C produces Cu +. The reaction of NO on the surface of copper-containing samples is discussed.