Abstract: An intermediate bulk storage container for the storage or transport of particulate catalyst material includes a vessel having an inner wall defining a containment volume for particulate catalyst material. The vessel has a cylindrical wall section, a top panel closing the upper end of the cylindrical wall section and a conical base section connected to and tapering inwardly away from the lower end of the cylindrical wall section. An opening in the top panel of the container receives the catalyst material and a closure member closes the opening. An air tight seal is formed when the opening is closed by the closure member. A gas duct is in fluid connection with the vessel for supplying an inert gas to the sealed container or removing gas from the vessel to place the container under a vacuum. The gas duct is closed by a valve for transit or storage.