Reactive extraction for preparation of hydrogen peroxide under pressure

The preparation of hydrogen peroxide from anthrahydroquinone by reactive extraction was investigated. The integration process of oxidation of anthrahydroquinone by air and extraction of hydrogen peroxide from the organic phase with water was carried out in a sieve plate column under pressure. The conversion of anthrahydroquinone increased with increasing pressure resulting in an increase of hydrogen peroxide concentration in the aqueous phase. However, no change in extraction efficiency of hydrogen peroxide was observed. A mathematical model for gas-liquid-liquid reactive extraction was established. In themodel, the effects of pressure and gas superficial velocity on reaction were considered.With increasing gas superficial velocity, the conversion of anthrahydroquinone increased, and the fraction of hydrogen peroxide extracted reached a plateau with a maximum of 72.94%. However, both the conversion of anthrahydroquinone and the fraction of hydrogen peroxide extracted decreased with increasing organic phase superficial velocity. __________ Translated from Petrochemical Technology, 2007, 36(1): 49–54 [译自: 石油化工]     

一种快速测定蒽醌含量的可见光谱方法

介绍了一种快速测定蒽醌含量的可见光谱方法。本方法是基于用连二亚硫酸钠(Na2S2O4)在碱性条件下将蒽醌(AQ)还原成蒽氢醌(AHQ),然后在505 nm处检测AHQ的吸光度而建立的。结果表明,将AQ转化成AHQ的最佳还原条件为:温度80℃,时间10 min,AQ、Na2S2O4和NaOH的摩尔比为1∶3∶50。本方法的相对标准偏差为2.01%;定量检测极限为2.26 mg/L;回收率在95.5%～100%。本方法完全满足商品蒸煮助剂中AQ含量检测的要求。     

加压反应萃取制过氧化氢

以空气为反应气体,在加压筛板塔中研究了空气-有机相-水三相蒽醌法反应萃取制H2O2的过程。提高操作压力,可以提高氢蒽醌的转化率,但不影响H2O2的萃取率,使水相中H2O2含量增大。计入加压及反应对气相表观流速的影响,建立了适用于气液液三相加压反应萃取的数学模型。模型计算结果与实验结果符合良好。当操作压力从0.1MPa升高到0.6MPa时,水相中H2O2含量最大增加3倍;随气相表观流速增大,氢蒽醌的转化率增大,H2O2的萃取率先增大后降低,最高为72.94%;随有机相表观流速增大,氢蒽醌的转化率和H2O2的萃取率均降低。