Synthesis of Adipic Acid through Oxidation of K/A oil and Its Kinetic
Study in a Microreactor System
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 adipic acid (i.e., 90%) was achieved just in 6
seconds at 85℃ 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 operating 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.