Process for preconditioning the carbon bed used in a method of converting refractorymetal oxychlorides

Claim 1

IN A METHOD OF CONVERTING REFRACTORY METAL OXYCHLORIDES, WHEREIN THE METAL PORTION THEREOF IS SELECTED FROM THE GROUP CONSISTING OF COLUMBIUM, VANADIUM, TUNGSTEN AND MOLYBDENUM, TO THE CORRESPONDING REFRACTORY METAL CHLORIDE BY HEATING A CARBON BED, WHEREIN THE CARBON IS SELECTED FROM THE GROUP CONSISTING OF AMORPHOUS CARBON AND CARBON MIXTURES CONTAINING AMORPHOUS CARBON, TO A MINIMUM TEMPERATURE OF 450*C. AND PASSING THROUGH SAID BED SAID REFRACTORY METAL OXYCHLORIDE AND A CHLORINATING AGENT, SAID AGENT BEING ABOUT 10 PERCENT IN EXCESS OF THE STOICHIOMETRIC AMOUNT REQUIRED FOR THE CONVERSION OF METAL OXYCHLORIDE TO METAL CHLORIDE, THE IMPROVEMENT WHICH COMPRISES PRECONDITIONING THE CARBON OF SAID BED BY HEATING THE CARBON TO A MINIMUM TEMPERATURE OF 200* C. AND PASSING CHLORINE THROUGH SAID CARBON UNTIL THE OFFGAS FROM SAID CARBON IS ESSENTIALLY CHLORINE.