Flow member and reaction vessel

A flow member constituting a reaction vessel that causes a supplied raw material liquid to pass through a catalyst layer and flow out as a reaction liquid, together with a first reaction unit and a second reaction unit, wherein

• the flow member being provided between the first reaction unit and the second reaction unit, the first reaction unit being provided inside with a first catalyst layer and including a first supply port for supplying the raw material liquid to the first catalyst layer from above and a first outflow port for allowing a reaction liquid generated from the raw material liquid flowing down the first catalyst layer to flow out downward, the second reaction unit being provided inside with a second catalyst layer, including a second supply port for supplying the reaction liquid to the second catalyst layer from above and a second outflow port for allowing the reaction liquid flowing down the second catalyst layer to flow out to outside, and the second reaction unit being provided below the first reaction unit,
• the flow member comprising:
• a flow path forming part, constructed by a tube wall, and a flow path being formed in the tube wall for causing the reaction liquid to flow down from an inside of the first reaction unit toward an inside of the second reaction unit;
• a liquid extractor, configured to extract the reaction liquid from the flow path in the tube wall to an outside of the flow path, wherein the liquid extractor includes:
• a liquid receiver, disposed in the flow path and configured to receive a part of the reaction liquid flowing down the flow path, and an extraction port, provided in the flow path forming part to extract the reaction liquid from the liquid receiver to the outside of the flow path;
• and
• an opening/closing part, configured to open and close the extraction port.