作　　者： ; ; ;

机构地区： 湖南理工学院化学化工学院

出　　处： 《稀土》 2005年第3期39-42,共4页

摘　　要： 硫酸钛掺杂La2O3后经高温焙烧制得一类稀土改性固体酸,用吸附吡啶的红外光谱表征其表面酸的性质,用合成丙酸丁酯的酸催化反应考察其催化活性。结果表明:固体酸中引入稀土元素,使得催化剂表面在保持Bronsted酸中心的同时,产生了新的Lewis酸中心;利用稀土的引入量不但可以调节固体酸表面B/L酸的比例,而且能提高固体酸中B酸的热稳定性。在催化合成丙酸丁酯化反应中,改性后的固体酸不但具有更好的酸催化活性,稀土含量少、反应后沉降快、易分离和回收、可重复使用多次,容易再生等优点,而且大大简化了反应的后处理工艺、产物无色、清亮透明。并获得催化剂制备优化条件为:镧含量5%,焙烧温度400℃。稀土改性后的固体酸是一种环境友好催化剂。 A new type of modified solid acid was prepared by calcination of titanium sulfate doped by lanthanum oxide. The acid property was characterized by FT-IR spectra of pyridine adsorbed on the solid acid surface. The catalytic activity was determined by esterification of propionic acid with butanol. The results showed that keeping up Brnsted acid property,the catalysts,simultaneously,had new Lewis acid centers. The ratio of B/L acid might be adjusted by changing content of Lanthanum. The heat stability of Brnsted acid on modified solid acid was enhanced greatly. In esterification,not only had modified solid acid many advantages,such as much better catalytic activity than immodified one,less content of rare earth,dropping more quickly after reaction,separated and recovered simply,reused for many times and regenerated easily,but also the technology of after-treatment was reduced and the reaction products were colorless and transparent. The optimum condition of catalytic preparation was obtained as follows: content of La_2O_3 5%,calcination temperature 400℃. Modified solid acid by rare earth was an environmentally friendly catalyst.

关 键 词： 氧化镧 改性 硫酸钛 酯化 环境友好催化剂

领　　域： [理学] [理学]