Kinetic and Thermodynamic Study of the Oxidation of Titanium(IV) Chloride at High Temperatures

摘要

The work has studied the thermodynamics and kinetics of titanium(IV) chloride oxidation with an argon-oxygen RF-plasma. Experiments to support the thermodynamic calculations were done and a kinetic model was proposed for the reaction system. Titanium(IV) chloride was injected into the tail flame of an argon oxygen plasma to produce titanium dioxide. The gas phase reactions were of major interest and the formation of different gas species was on-line recorded with a mass spectrometer. With the mass spectrometer argon mass number per charge (20, 40), oxygen (16, 32), nitrogen (14, 28), chlorine (35, 70, 72), chloride monoxide (51), titanium oxychloride (100, 135) and titanium tetrachloride (155) were detected. Chlorine monoxide and titanium oxychloride are playing a major part in the kinetic model. Supported by the experiments, a kinetic model for the oxidation of titanium(IV) chloride is presented. A chain reaction mechanism is suggested. With the available information it is not possible to determine a single step as a rate-determining for the proceeding of the reaction. It may be assumed that certain additional substances help formation of TiClx-radicals in the earlier stages of the reaction. The proceeding of the reaction in an adiabatic reactor channel is also calculated.