Health & Environmental Research Online (HERO)


Print Feedback Export to File
8340714 
Journal Article 
Process improvement on synthesis of menadione sodium bisulfite 
Song, C; Shen, H; Zhao, J; Wang, L; Xu, H 
2007 
24 
5 
21-24 
Chinese 
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 solution. 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 sodium bisulfite 1 : 1. 45, reaction temperature 40 °C 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. 
2-methyl-1; 4-naphthoquinone; Menadione sodium bisulfite; Process improvement; Sodium bisulfite