| 摘要 |
In the nitration of organic compounds involving heating or cooling of one or more of the reagents, temperature-controlling media are employed for the whole of such heating or cooling which are in indirect contact with the reagents and are inert to them or react to form innocuous products. Explosion or fire through leakage from the heating or cooling system is thereby avoided. The media may consist of substances present in the reagents. Thus in nitrating glycerine or glycol, the cooling medium is nitric or sulphuric acid or a mixture thereof having a water content substantially that of the nitrating acid. The cooling medium may then be used to feed the nitrator. Inert saturated aliphatic hydrocarbons or halogenated hydrocarbons, or solutions of nitrates and/or sulphates can also be used. These are circulated between the cooling coils, jackets, or the like of the nitrator and a refrigerating machine. Alternatively, an inert gas such as carbon dioxide or air may be employed. For heating the glycerine, glycol, or mixture thereof, these compounds themselves can be employed. The process is applicable to the nitration of benzene, toluene, xylene or other hydrocarbons. |
