FIELD: synthesis of acetic acid.
SUBSTANCE: The present invention relates to a method for the synthesis of acetic acid by carbonylation of low-pressure methanol, including: (1) the introduction of methanol and CO into a reactor without stirring to conduct a carbonylation reaction in it in the presence of a catalyst, the supply of a liquid-phase part from the middle part of the reactor without stirring into an instantaneous evaporation evaporator for instant evaporation, thus separating it to obtain a liquid-phase (2) the implementation of heat exchange between the liquid-phase component and the instantaneous evaporation heat exchanger of the mother liquor and after heating the supply of the liquid-phase component to the secondary instantaneous evaporation, thus separating it to obtain a secondary liquid-phase component and a secondary gas-phase component; (3) the supply of the primary gas-phase component and the secondary gas-phase component obtained by separation, into a catalyst trap from which the captured catalyst is extracted and recirculated into an instantaneous evaporation evaporator, and then the gas-phase components are fed into the distillation column of light components for rectification, thus separating them to obtain a light component and a heavy component; (4) recirculation of liquid-phase components obtained in stage (1) and stage (2), back into the reactor without stirring for the reaction; (5) feeding the heavy component obtained in step (3) into the rectification column of heavy components for rectification, thus separating it with the production of acetic acid.
EFFECT: The present invention enables to completely separate the liquid by using the reaction heat, reducing inefficient circulation and saving energy and steam consumption.
1 cl, 1 dwg, 9 ex
