The Study Of Vapour Permeation Membrane Reactor On Synthesis Of Naproxen Ketal Intermediate

As one of the four major analgesic anti-inflammatory drug, naproxen is widely used by the method of1,2-aryl rearrangement to synthesis, but this method suffers from some issues:such as, low utilization rate of raw materials, causticity for equipments, high energy consumption and production costs. The study found that the byproduct of water in the synthesis process of naproxen ketal intermediates, which not only has certain inhibition leads to lower its yield itself, but also has the serious influence for the next step of rearrangement reaction, So how to rapidly removal by-product water in the process of synthetic naproxen ketal intermediates, break the reaction equilibrium limit, and increase the efficiency of naproxen ketal intermediates is of great significance.According to the characteristics of naproxen ketal reaction process,the researchers adopt reaction separation coupling technology for the synthesis of naproxen ketal intermediates, such as the azeotropic reaction distillation. But there is still a high reaction temperature, dosage of solvent, high energy consumption. This paper applies vapor permeation membrane reactor to the synthesis of naproxen ketal synthesis intermediates. Use lab homemade PVA/PES composite membrane as vapor permeation membrane, and using the technology of split type gas cycle vapor permeation membrane reactor to synthesis naproxen ketal intermediates. We optimized the reaction conditions of naproxen shrinkage ketone reaction used in vapor permeation membrane reactor. In reaction temperature90℃, reaction time12h, initial molar ratio of materials nNPG:nMBPN=1-75:1, the mass of catalyst p-toluene sulfonic acid is9%of the quality of MBPN and the raw material MBPN conversion is83%, synthetic effect is significantly higher than the batch reactor.Through the toluene/water system simulation naproxen ketal reaction system, investigates gas liquid mass transfer reinforcement means, such as circulation gas, pore size of air distribution, liquid level and the state of liquid, which have the water separation effect of vapor permeation membrane reactor for toluene/water system. Results show that the introduction of gas-liquid mass transfer reinforcement method can strengthen the separation of the water in the toluene/water system, to achieve rapid removal of water at lower temperatures.Adopting external vapor permeation membrane reactor for naproxen ketal intermediates in the synthesis, through optimizing vapor permeation membrane reactor reaction unit operation conditions, and the introduction of gas-liquid mass transfer reinforcement method, and Under the temperature of90℃, the reaction time of12h, the key raw material MBPN conversion is92%, naproxen BMNDD ketal intermediates yield is88%, the synthesis effect is much higher than batch reactor, and close to azeotropic distillation reaction at114℃of naproxen ketal intermediates.The results showed that the vapor permeation membrane reactor can efficient synthesis naproxen ketal intermediates at lower temperatures, and to avoid the extensive use of water carrying agent, It has important research value and significance of high efficiency and low energy consumption, realize the synthesis of naproxen.