Patent ID: 7597529

Claim:
A method of charging a vertical tube having an internal diameter of 50 mm or less with catalyst particles, the method comprising: introducing a filling aid into the vertical tube, where the filling aid comprises a flexible elongated body and a ratio of the cross section of the flexible elongated body to the cross section of the tube is from 0.003 to 0.08, and (1) the filling aid has no elements which extend radially outward from the flexible body, or (2) the filling aid comprises spacers which are arranged at a distance from one another and extend perpendicular to the longitudinal direction of the filling aid, wherein the projection of the spacers onto a plane perpendicular to the longitudinal direction of the filling aid has no larger area than a cross section of the flexible body, and the filling aid has no other elements than said spacers, which extend radially outward from the flexible body; introducing the catalyst particles into the tube, and withdrawing the filling aid during introduction of the catalyst particles so that the lower end of the filling aid is always above the fill height of the catalyst particles in the tube, thereby obtaining a charged vertical tube having a bulk density of the packed catalyst particles and a pressure drop lower than the bulk density and the pressure drop of the vertical tube in which the catalyst particles are introduced without the filling aid for charging the vertical tube having the internal diameter of 50 mm or less with the catalyst particles.