Process control in production of acetic acid via use of heavy phase density measurement

1. Field of the Invention A process for monitoring and controlling reactor conditions during the production of acetic acid by the catalyzed carbonylation of methanol is provided. The process of the present invention comprises measuring the density of the heavy phase of the light ends distillation column in the purification system of the carbonylation process. The density measurement is used to adjust the feed of methanol and/or to regulate the temperature in the reaction zone to optimize reactor conditions. The density measurement may also be used to adjust other parameters in the reactor system. The invention is also directed to the system for manufacturing acetic acid based on the process control procedure described.