Method for producing 1,3-butadiene

A method for producing 1,3-butadiene comprising:

• a step (A) of performing an oxidative dehydrogenation reaction, with a molecular oxygen-containing gas in a presence of a metal oxide catalyst, of a raw material gas, which contains n-butene, to obtain a produced gas containing 1,3-butadiene;
• a step (B) of cooling the produced gas obtained in the step (A);
• a step (C) of separating the produced gas, which has been subjected to the step (B), into molecular oxygen and inert gases, and other gases containing 1,3-butadiene by selective absorption into an absorption solvent;
• and
• a step (D) of separating the absorption solvent, which has been obtained in the step (C), that has absorbed the other gases containing 1,3-butadiene, to obtain a 1,3-butadiene liquid, containing 1,3-butadiene, and the absorption solvent, wherein
• the step (D) includes:
• a step (D1) of separating the absorption solvent, which has absorbed the other gases containing 1,3-butadiene, into an absorption solvent that does not substantially contain an absorption component including the other gases containing 1,3-butadiene and an absorption solvent that contains the absorption component;
• a step (D2) of separating the absorption solvent, which has been obtained in the step (D1), that contains the absorption component into an absorption solvent that contains a reaction by-product and the 1,3-butadiene liquid containing 1,3-butadiene;
• and
• a step (E) of purifying the absorption solvent, which has been obtained in the step (D2), that contains the reaction by-product.