摘要 |
An object of the present invention is to provide a method in which, when a steam ejector is used as a decompression apparatus for a vacuum distillation process for an easily polymerizable compound, the steam ejector is prevented from being occluded due to polymerization of the easily polymerizable compound. Another object of the present invention is to provide a method for manufacturing an acrylic acid that is an easily polymerizable compound, using the above-described method. The above object is accomplished by a method for manufacturing an acrylic acid, which comprises a step of executing vacuum distillation, using a steam ejector, on an acrylic acid resulting from gas-phase catalytic oxidation using propane, propylene, or acrolein as a material, wherein the vacuum distillation step includes a step of heating an outer surface of the steam ejector. Furthermore, the other object is accomplished by a method for vacuum distillation of an acrylic acid or an acrylic ester using a steam ejector, which comprises a step of heating an outer surface of the steam ejector. |