M. Sh. Bafghi - ۱ School of Metallurgy and Materials Engineering, Iran University of Science & Technology, Tehran, Iran.
A. Yarahmadi - ۲ Department of Mining Engineering, Faculty of Engineering, Yazd University, Yazd, Iran.
A. Ahmadi - ۳ School of Metallurgy and Materials Engineering, Iran University of Science & Technology, Tehran, Iran.
H. Mehrjoo - ۳ School of Metallurgy and Materials Engineering, Iran University of Science & Technology, Tehran, Iran.

Abstract: the reduction agent. Pellets of barite ore containing about ۹۵% BaSOtemperature, time, ore grain size and the type and grain size of the carbon materials. Graphite, coke and charcoal havebeen used as the reducing agent and the reduction experiments have been performed in the temperature range of ۹۲۵-۱۱۵۰ °C. Apart from conducting the experiments using pellets made of ore powder, kinetic analysis of the experimentaldata by use of the reduced (dimensionless) time method has been another unique feature of the present study.Experimental results show that grain size of either carbon material or barite ore has not appreciable effect on thereaction rate. Kinetic analysis of the experimental data revealed the rate is strongly controlled by the chemical reactionof carbon gasification (Boudouard reaction). The reaction rate is very considerably related to the type of carbonmaterial so that the activation energy varies from ۱۵.۶ kcal.molkcal.molgasification.The present study deals with the reduction of barium sulfate (Barite) to barium sulfide by use of carbon as۴ has been reduced under different conditions of-۱ for charcoal to ۲۶.۳ kcal.mol-۱ for graphite and ۲۰.۸-۱ for coke. This behavior provides further support for the postulated reaction mechanism, i.e., carbon

Keywords: Barite, carbothermic reduction, kinetic analysis, carbon gasification, activation energy.