更新时间：05-31 （我爱小小）提供原创文章
摘 要：2,6-二氟苯甲酸是一种重要的农药，医药的中间体，也是比较广泛的有机溶剂。在现代社会中运用广泛。本设计采用的是釜的连续生产，生产的含量达到99.7%2,6-二氟苯甲酸。制取该产品，分为三个步骤进行。第一步是氟化反应，将原料2,6-二氯苯甲腈、KF和催化剂DMF在氟化釜中进行氟化反应，加热升温回流反应时间为7个小时左右，反应完成后在经过过滤、洗滤渣，得到2,6-二氟苯甲腈及DMF混合溶液。第二步是脱溶过程，将第一步的产物放入蒸馏釜中蒸馏，将DMF去除得到较纯的2,6-二氟苯甲腈。第三步反应是水解反应，将第一步生产出的2,6-二氟苯甲腈投入水解釜中，投入20%的NaOH.，控制反应温度在90°C，反应时间为8-9个小时。随后加入70%的H2SO4。然后经过离心、重结晶及烘干，最后得出产品2,6-二氟苯甲酸。
关键词：2,6-二氟苯甲酸； 2,6-二氟苯甲腈； 2,6-二氯苯甲腈； 氟化钾；
N,N-二甲基甲酰胺
Abstract：2,6-difluorobenzoic acid, which is widely used in modern society, is a kind intermediate of important of pesticides and pharmaceuticals, and it is also broadly seen as the organic solvent. This design selects the cauldron’s continuous production, in which the purity of 2, 6-difluorobenzoic acid may reach to 99.7%. The continuous production can be divided into three steps. The first step is the fluorination reaction: Mix the raw materials, 2, 6-dichlorobenzonitrile, KF and the catalyst DMF together in the fluorination reactor, and then heat for the refluxing reaction for about seven hours. Later after filtering and washing the residue, the mixed solution of 2, 6-difluorobenzonitrile and DMF can be received. The second step is the exsolution: Put products from the first step into the distillating reactor to distill, and then remove the DMF to get purer 2, 6-difluorobenzonitrile. The third step is the hydrolysis reaction: Put 2, 6-difluorobenzonitrile made in the first step into the hydrolysis reactor, mixed up with the 20% NaOH. Let the reaction temperature stay at 90 ℃ for about 8 to 9 hours. Subsequently join the 70% H2SO4 into the reactor. Later after the centrifugation, recrystallization and drying, we finally get the product 2, 6-difluorobenzoic acid.
Key words：2,6-difluorobenzoic acid; 2,6 - difluorobenzonitrile; 2,6 – dichlorobenzonitrile; potassium fluoride; N,N-dimethylformamide