| abstract |
(57) [Summary] (with correction) [PROBLEMS] To reduce the temperature distribution of a heat medium in a reactor and suppress the generation of hot spots. SOLUTION: In a reactor 401 including a plurality of reaction tubes 404 and a baffle plate capable of changing a moving direction of a heat medium introduced into a reactor shell, a space portion in which no reaction tubes are arranged is provided at the center. A multitubular reactor having at least one or more heat medium circulation passages 431a to 431c between the outer peripheral portion and the central portion, and performing catalytic gas phase oxidation using the reactor. A method for producing (meth) acrylic acid and / or (meth) acrolein. |