Selective chlorination of iron from low grade titanium ore in a fluidized bed reactor.

摘要

The selective chlorination of iron from low grade titanium ore in a fluidized bed reactor has been investigated. This research included the measurement of basic kinetics of the selective chlorination for ilmenite using carbon monoxide gas as a reducing agent in a shallow fluidized bed, analyses of the upgrading of titaniferous magnetite by carbochlorination in a fluidized bed, and a formulation of mathematical model.; It was determined that the basic kinetics of chlorination followed a logarithmic rate expression with an activation energy of 37.2 kJ/mol. The partial pressure of carbon monoxide was found to affect the chlorination rate more strongly than that of chlorine. There was no particle size effect on the chlorination. A reaction mechanism in which iron in ilmenite reacts with chlorine first and then the liberated oxygen is removed by carbon monoxide is proposed.; In the carbochlorination of titaniferous magnetite, temperatures lower than 973 K were favorable for the selective chlorination of iron. Through the application of the shrinking unreacted core model the rate was found to be first order with respect to chlorine and the effects of particle size and the amount of carbon added was determined. By the modification of the two-phase fluidized-bed model, three mathematical models which can describe the behavior of gas and solid movement in a fluidized bed as well as interpret the experimental results for the selective chlorination of iron were formulated. Predictions from these models were compared with experimental results, which produced a satisfactory agreement.