复合SO_4^(2)-/ZrO_2固体超强酸催化剂的结构表征

Characterization of SO 2- 4/ZrO 2 Solid Superacid Catalyst Modified with Transition-Metal Oxides.

制备了一定焙烧温度和焙烧时间下的不同浓度系列的 Ｓ Ｏ２ －４ ／ Ｚｒ Ｏ２ － Ｆｅ２ Ｏ３ 、 Ｓ Ｏ２ －４ ／ Ｚｒ Ｏ２ － Ｎｉ Ｏ 及 Ｐｔ／ Ａｌ２ Ｏ３ － Ｓ Ｏ２ －４ ／ Ｚｒ Ｏ２ 固体超强酸催化剂，并用 Ｘ Ｒ Ｄ 技术研究了温度、浓度及不同金属氧化物的引入对于 Ｚｒ Ｏ２ 的晶型转换的影响。结果表明，高温焙烧对 Ｚｒ Ｏ２ 晶相的生成起着决定性作用，温度升高则对四方相 Ｚｒ Ｏ２ 的存在有抑制作用；金属氧化物的引入对 Ｚｒ Ｏ２ 晶型的形成有定向诱导作用，使样品中四方相 Ｚｒ Ｏ２ 的含量明显增加，催化剂的活性及稳定性增强；机械混合对于焙烧过程中已形成的晶相有破坏作用。

he solid superacid catalysts of SO 2- 4/ZrO 2-Fe 2O 3,SO 2- 4/ZrO 2-NiO and Pt/Al 2O 3-SO 2- 4/ZrO 2 with different concentrations at the definite temperature and time of calcination are prepared. The effects of the temperature of calcination, the concentration of metal oxide and the incorporation of different kinds of metal oxide for transformation of ZrO 2 crystal phase are studied by using XRD method. It is found that the calcination at high temperature resulted in the formation of the crystal phase of ZrO 2, and the existence of the tetragonal crystal phase of ZrO 2 is restrained when the temperature of calcination is increased. The incorporation of metal oxide had directional induction for the formation of the crystal phase of ZrO 2, and results in the remarkable increase of the content of the tetragonal crystal phase of ZrO 2 as well as the activity and stability of catalysts. While the mechanical mix has damage function to the formed crystal phase of ZrO 2. SUBJECT HEADINGS