间硝基苯磺酸钠清洁生产工艺研究

利用从发烟硫酸中蒸出的SO3磺化硝基苯,并通过盐析使磺化产物间硝基苯磺酸成盐析出,母液经中和、回收水合硫酸钠(副产元明粉)后作盐析剂全部循环回用,实现了整个生产过程的密闭循环,做到了污染物的零排放。与传统工艺比较,间硝基苯磺酸钠产品含量可提高到98.6％,收率以硝基苯计增加15％以上。副产品硫酸和元明粉均属有用的化工原料,社会、经济和环境效益明显。

New Technique for the Cleaning Production of Sodium m-Nitrobenzene Sulfonate

Sodium m-nitrobenzene sulfonate was manufactured by first sulfonating nitrobenzene with sulfur trioxide evaporated from sulfuric acid and then salting out the resultant of sulfonation,nitrobenzene sulfonic acid,as its corresponding sodium salt.Subsequently, the mother solution was neutralized to recover hydrated sodium sulfate ( afterwards converted to anhydrous sodium sulfate). After the separation of the hydrated sodium sulfate, the remaining mother liquor was recyded so as to achieve a close circulation of the whole technological process and a zero release of pollutants. In comporison with conventional technologies, this method distinguishes itself by its product's high purity of 98.6% and a 15% increase in yield. Moreover, the by-products sulfuric acid, anhydrous sodium sulfate, etc, are all useful chemical raw materials. So the new production technique for Sodium m-nitrobenzene sulfonate can provide significant social, economic, and environmental benefits.