Design and control of entrainer-assisted reactive distillation for N-propyl propionate production

- We study an entrainer assisted reactive distillation process (E-RD) for the N-propyl propionate production.
- This E-RD process can save 46.11% of TAC compared with the two-column process.
- The E-RD process can reduce the reboiler duty by 41.40% compared with the two-column process.
- Two control structures are proposed to control the E-RD process for the N-propyl propionate production.

An entrainer-assisted reactive distillation process is proposed to produce high-purity N-propyl propionate from propionic acid and N-propanol. The E-RD process can take advantages of both the heterogeneous azeotropic distillation (HAD) and reactive distillation (RD). Cyclohexane is selected as the proper entrainer in the E-RD process. And the E-RD process is optimized by calculating the minimum total annual cost (TAC). The optimal results reveal that the E-RD process can save 46.11% of TAC and 41.40% of reboiler duty compared with the two-column process. Furthermore, two control structures for the E-RD process are considered. The dynamic performances demonstrate that the improved control structure (CS2) can solve the problem of disturbances and maintain the product purities close to the set points with small deviations and short settling times.