Cleaning finely divided, fumed metal oxide

A process for removing adhering halide in finely divided metal oxide particles by means of steam, wherein - the metal oxide particles are applied in the upper part of an upright column and move by gravity down, - the water vapor at the lower end of the column is abandoned, the metal oxide particles and water vapor are conducted in countercurrent, - freed from halide radicals metal oxide particles are withdrawn at the bottom of the column, - water vapor and halide radicals are withdrawn at the top of the column, wherein - the column is heated so that the temperature difference T -T - the metal oxide particles have a min residence time in the column from 1 second to 30th