Yang Han,Yuanyuan Liu,Shiwei Wang,Xuehui Ge,Xiaoda Wang,Ting Qiu
Tonalid, an important fragrance ingredient with widespread application, was synthesized via two Friedel-Crafts reactions, which were catalyzed by AlCl 3 . The traditional tonalid production was conducted in batch stirring tank reactors, suffering from low production capacity and the safety hazard of temperature runaway. To solve these problems, the continuous-flow technologies were developed for the high-efficiency and intrinsically safe synthesis of tonalid in microreactors. Catalyst AlCl 3 was neatly homogenized in proper solvents by forming complex with reactant, which was a necessary step for the continuous synthesis in microreactors. Several reaction conditions, including reactant molar ratio, catalyst concentration, temperature, and microchannel hydrodynamic diameter, were investigated for the two Friedel-Crafts reactions in microreactors. At optimized conditions, the yields of the two Friedel-Crafts reactions were 44.15% and 97.55%, respectively. In comparison with the batch reactors, the reaction times of these two reactions could both be reduced by nearly two thirds in microreactors at the similar yield.
2-Methyl-2-cyclopentenone (MCP) is the main by-product of the newly developed heterogeneous catalysis process for producing crotonaldehyde, which serves as an important intermediate for drug synthesis. However, how to recover and purify MCP from the product mixture is not known. To decipher this, a computer-aided process based on the measured phase-equilibrium data was developed. The improved Rose–Williams equilibrium kettle was used to measure the vapor–liquid equilibrium data for MCP–crotonaldehyde and MCP–water. Surprisingly, MCP and water formed a minimum azeotrope, which aided its own recovery from its dilute solution. The mole fraction of MCP in the azeotrope was 9.1%, the mole fraction of water was 90.9%, and the azeotropic temperature was 96.8 °C. Equilibrium data from the two binary systems were correlated using the Wilson and NRTL activity coefficient models. The NRTL-RK model was selected to simulate the process for recovering and purifying MCP. A two-column process was developed and optimized in this study, and the aim of effectively utilizing the by-product MCP was achieved with this process.
危险品化学品经营许可证（带存储）