An effect of lubricant on densifying the form of graphitized carbon black powder was investigated, using orthoboric acid as a densifying agent. The carbon black was synthesized from CO in Boudouard's reaction with Fe catalyst. The iron contamination was removed by means of hot extraction before pressing the carbon black powder into a pressed form. The density of the form was studied by means of densimetric and conductometric measurements. On the basis of these results a friction and lubrication model was used to explain the process of densification. The orthoboric acid due to its lubrication properties effectively favors the displacement of pores from the carbon black form. (C) 2002 Elsevier Science Ltd. All rights reserved.