使用1,8-萘二甲酸酐为原料,采用亨克尔法,以碳酸锌做催化剂、萘和碘化钾为助剂,在二氧化碳气氛中进行反应,通过异构化反应制备2,6-萘二甲酸.探讨了反应温度、反应时间、催化剂用量、反应压力、搅拌速度、助催化剂和助剂用量对异构化转位反应的影响.结果表明:根据正交实验确定了1,8-萘二甲酸二钾盐异构化转位反应的较优工艺,各反应因子反应温度、催化剂用量、反应时间、反应压力、搅拌速度对亨克尔异构化转位反应影响依次减弱；反应温度为380℃、反应时间为2.5h、催化剂摩尔分数为0.06％(相对于1,8-萘二甲酸二钾盐)、反应压力为2.5 MPa、搅拌速度为400 r/min、助催化剂和助剂摩尔分数为0.05％(相对于1,8-萘二甲酸二钾盐).通过红外光谱和核磁共振分析确定反应产物为2,6-萘二甲酸.%Using 1,8-naphthalenedicarboanhydride as raw material, 2,6-naphthalenedicarboxylic acid was synthesized by Hen-kel isomerization reaction. The reaction proceeded using zinc carbonate as catalyst, naphthalene and potassium iodide as additives in carbon dioxide atmosphere. The effects of reaction temperature and time, catalyst amount, reaction pressure, stirring speed, cocatalyst and additive amount on the isomerization interconversion reaction were discussed. The results showed that the influential factors on the Henkel isomerization interconversion reaction from high to low in turn were reaction temperature, catalyst a-mount, reaction time, reaction pressure and stirring speed. The process conditions of dipotassium 1,8-naphthalenedicarboxylate isomerization interconversion reaction were optimized by orthogonal experiments as followed: reaction temperature 380 ℃, time 2.5 h, 0.06% catalyst by mole fraction based on dipotassium 1,8-naphthalenedicarboxylate, reaction pressure 2.5 Mpa, stirring speed 400 r/min, 0.05% cocatalyst and additives by mole fraction based on dipotassium 1,8-naphthalenedicarboxylate. The reaction product was dedermined as 2,6-naphthalenedicarboxylic acid by infrared spectroscopy and nuclear magnetic resonance.
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