对硝基乙苯是氯霉素生产中的主要原料,但乙苯的硝化都是得到邻位和对位两种异构体,因此如何提高邻对位异构体的比例(p/o 值)是十分关键的。目前国内多采用混合酸硝化法,其 p/o 值一般只有1.18左右,本文采用催化硝化法可使产物的 p/o 值 P-nitroethylbenzene is the main raw material in the production of chloramphenicol. However, the nitration of ethylbenzene results in both ortho and para isomers. Therefore, how to increase the ratio of ortho para isomers (p / o value ) Is very crucial. At present, the domestic use of mixed acid nitration method, the p / o value is generally only about 1.18, this paper can be used to promote the catalytic nitration of p / o value