Abstract: p-Menthane-1,8-diamine was prepared by hydrolysis of p-menthane-1,8-diacetamide in a sealed reaction kettle with n-butanol as solvent and sodium hydroxide as catalyst. While the amount of raw material was 0.1 mol, n-butanol was 150 mL, the molar ratio of the raw material to the catalyst was 1:5, the reaction temperature was 175℃, the system pressure spontaneously increased to 0.35-0.4 MPa, and the reaction time was 18 h, a good result was obtained with 100% conversion of raw materials and more than 96% selectivity for the product, the GC content of which was 96.47%. Compared with the atmospheric process, the reaction time of the sealed process was shortened by 50%, the product selectivity was increased by 20 percentage points. Besides, good results were obtained when the inventory was increased by 10 times, furthermore, the adding proportion of solvent could be furtherly decreased. The product from sealed process was separated and purified by vacuum distillation while vacuum rectification for product from atmospheric process, the results showed that the separation and purification time of vacuum distillation was reduced by 7/8, solvent was recovered by 5.3 percentage point and could be reused, and the product yield was improved by 55.7 percentage point to 85.6% with the purity of 96.51%.

Key words: p-menthane-1,8-diamine, p-menthane-1,8-diacetamide, base catalysis, sealed hydrolysis