对苯二酚制备中酸回收套用研究

Research into the Reuse of the Waste Sulfuric Acid in Preparation of Hydroquinone by Diazotization and Hydrolysis of P-aminophenol

分析了以对氨基苯酚为原料经重氮化、水解法制备对苯二酚的机理及方法,研究了对苯二酚制备过程中的主要工作介质硫酸进行水解反应和重氮化反应的回收套用方法。结果表明,浓缩回收后的废硫酸总含盐量小于15%,将其多次用于水解反应,是可行的。酸回收后,其中的盐含量小于1.7%,HQ含量小于0.05%,尿素、硫脲含量维持较低数值下,将其套用于重氮化反应,同样可行。这一研究结论为对氨基苯酚重氮化水解法制备对苯二酚工业化生产奠定了基础。

The thesis introduces the mechanism,process and method for the preparation of hydroquinone by diazotization and hydrolysis of p-aminophenol.In particular,the reuse of the waste sulfuric acid which is the main working medium for the diazotization and hydrolysis is discussed.The results showed that the waste sulfuric acid which is enriched can be repeatedly used in the hydrolysis when the total salt content is less than 15%.And it is feasible that the waste sulfuric acid being enriched is reused in the diazotization when the total salt content less than 1.7%,HQ content less than 0.05%,with urea and thiourea content maintaining lower level.The research results lay the basis for the industrialization of the preparation of hydroquinone by diazotization and hydrolysis of p-aminophenol.