LAUSR

The synthesis of methyl anthranilate (MA) from phthalimide is widely used in the production of sodium saccharin because of its accessible raw materials and stable products. In the traditional semi-batch production mode, difficulties to control the temperatures of strong exothermic reactions and the large energy consumption greatly limit its wide applications and sustainable development. In this paper, a new method of MA synthesis by microchannel reactor is proposed, which realizes the transformation of MA synthesis from semi-batch production to continuous production.The effects of different parameters on the conversion rate of raw materials and the purity of products were studied in the experiment part. For comparison, specific experiments were both set up in semi-batch and continuous production process. The optimal synthesis condition of the continuous process is finally determined as below: the molar ratio of the reactants (phthalimide: sodium hypochlorite: methanol) is 1: 1.1: 3.7; the reaction temperature is 0 °C; the reaction time is 97 s. The MA with high yield and purity (80.3 % and 98.5 %) are successfully synthesized. Compared with the semi-batch process, the yield and purity of the continuous products are increased by 5.1 % and 1.2 %. This study provides fundamental data for process optimization, clean production and energy consumption reduction by continuous process. This continuous synthesis method provides a more safe, efficient and energy-saving production mode for industrial production.