Synthesis of adipic acid (AA) through the oxidation of cyclohexanol and cyclohexanone (K/A oil) with nitric acid was conducted in a capillary microreactor system. Effects of the temperature, the nitric acid concentration, the volumetric flow rate ratio of nitric acid to K/A oil, and the capillary length on the selectivity and the product yield were investigated systematically to achieve optimal reaction conditions. Notably, a high yield of AA (i.e., 90%) was achieved just in 6 seconds at 85°C with the use of 55 wt% nitric acid. Gas components produced in this oxidation process and its total volumetric flow rate were determined under various operational conditions, which was beneficial for reaction mechanism characterization and process optimization. Finally, a kinetic model was established, which was of crucial theoretical significance and practical value for optimizing the reactor design and better understanding such fast and highly exothermic multiphase processes with abundant gas production.

中文翻译：

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K / A油氧化合成己二酸及其在微反应器系统中的动力学研究

在毛细管微反应器系统中，通过用硝酸氧化环己醇和环己酮（K / A油）合成己二酸（AA）。系统地研究了温度，硝酸浓度，硝酸与K / A油的体积流量比以及毛细管长度对选择性和产物收率的影响，以达到最佳反应条件。值得注意的是，使用55重量％的硝酸，仅在85℃下仅在6秒内就获得了高的AA产率（即90％）。在各种操作条件下测定了该氧化过程中产生的气体成分及其总体积流量，这有利于反应机理的表征和工艺优化。最后，建立动力学模型，