亚硫酸氢钠甲萘醌合成工艺改进

PROCESS IMPROVEMENT ON SYNTHESIS OF MENADIONE SODIUM BISULFITE

传统亚硫酸氢钠甲萘醌(MSB)合成原料2-甲基-1,4-萘醌(2-MNQ)中含有6-甲基-1,4-萘醌(6-MNQ),致使产品含量较低。为提高产品质量,对原料中的6-MNQ进行了分离去除,在正己烷溶剂中和NaHSO_3反应合成MSB。考察了原料配比、反应温度、反应时间等因素对合成MSB的收率和纯度的影响,最佳工艺条件为:n(2-MNQ)与n(NaHSO_3)=1∶1.45,反应温度40℃,反应时间4 h。改进工艺后MSB的收率提高到81%,质量分数大于98%。

In the synthesis of menadione sodium bisulfite （MSB）, the traditional raw material 2-methyl-1, 4-naphthoquinone （2-MNQ） contains 6-methyl-1, 4-naphthoquinone （6-MNQ）, resulting in lower content of the product. To improve product quality, 6-MNQ was separated and removed from the mixture of 2-MNQ, and then 2-MNQ reacted with sodium bisulfite to form MSB in n-hexane solu- tion. The ratios of raw materials, reaction temperature and reaction time on the yield and purity of MSB were investigated. The optimum conditions were found as follows： mole ratio of 2-MNQ to sodi- um bisulfite 1：1.45, reaction temperature 40℃ and reaction time 4 h. The results showed that with the improved process, the yield of MSB was above 81%, and the purity of MSB was above 98%. The improved process is practical and can be used in industry with the production cost being reduced.