申请人:Vertac Chemical Corporation
公开号:US04346248A1
公开(公告)日:1982-08-24
A process for the preparation of 2,4,5-trichlorophenol and 2,4,5-trichlorophenoxyacetic acid free of 2,3,7,8-tetrachloro-dibenzo-p-dioxin contamination by the steps of nitrating 1,2,4-trichlorobenzene, reducing the resulting 1,2,4-trichloro-5-nitrobenzene, diazotizing the resulting 2,4,5-trichloroaniline, hydrolyzing the resulting 2,4,5-trichlorobenzenediazonium salt and recovering 2,4,5-trichlorophenol. The 2,4,5-trichlorophenol is reacted with monochloroacetic acid to give 2,4,5-trichlorophenoxyacetic acid. Both the 2,4,5-trichlorophenol and the 2,4,5-trichlorophenoxyacetic acid produced by the process are analytically free of 2,3,7,8-tetrachloro-dibenzo-p-dioxin in analytical tests sensitive to 1 part per billion.
一种制备2,4,5-三氯酚和2,4,5-三氯苯氧乙酸的方法,不含2,3,7,8-四氯二苯并二噁英污染物。该方法包括以下步骤:硝化1,2,4-三氯苯,还原所得的1,2,4-三氯-5-硝基苯,重氮化所得的2,4,5-三氯苯胺,水解所得的2,4,5-三氯苯重氮盐,并回收2,4,5-三氯酚。2,4,5-三氯酚与单氯乙酸反应,生成2,4,5-三氯苯氧乙酸。该方法制备的2,4,5-三氯酚和2,4,5-三氯苯氧乙酸在灵敏度为每亿分之一的分析测试中均不含2,3,7,8-四氯二苯并二噁英。