| 摘要 |
The present invention provides a process in which acetic acid is produced while inhibiting the concentrations of hydrogen iodide and acetic acid from rising in an acetaldehyde distillation tower. The process comprises: a step in which methanol is reacted with carbon monoxide; a step in which the reaction mixture is fed to a flasher and separated into a volatile component (2A) and a lowly volatile component (2B); a step in which the volatile component (2A) is fed to a distillation tower and separated into an overhead fraction (3A) comprising methyl iodide, acetic acid, methyl acetate, water, acetaldehyde, and hydrogen iodide and a fraction (3B) comprising acetic acid, which is recovered; and a separation step in which the condensed overhead fraction (3A) is fed to an acetaldehyde distillation tower and a liquid to be treated which includes the overhead fraction (3A) is separated into a low-boiling component (4A) containing acetaldehyde and a high-boiling component (4B). In the separation step, the liquid to be treated contains methanol and/or dimethyl ether in a concentration of 0.1-50 wt.% and is distilled. |
