| Carbochlorination is an important technology used in metallurgical industry for extraction of metals from their concentrates. Refractory metal compounds (usually oxides) can be chlorinated in the presence of a reducing agent (e.g. C or CO) to form metal chlorides which are volatile in the operation temperatures. These gaseous chlorides are carried off by the exit gas stream from the solid bed and then condensed and purified to obtain pure metal chlorides. The pure metal chlorides are further processed to get pure metal compounds or reduced to get pure metals.; Compared with the old solution methods, the chlorination process is simple. It generates less waste and gives products of high purity and quality. However, systemic study on the carbochlorination reactions has not been done. More applications of this method may be explored. Some problems which exist in the commercial processes need to be solved or improved.; The research work in this dissertation includes: experimental investigations of the chlorination of various metal compounds to determine the possibility of extracting the metals from these compounds; application of the carbochlorination method to the recycling of fly ash carbon; systemic study on kinetics and thermodynamics of several important reaction systems in pigment and metallurgical industries; development of a low temperature process to solve the problems caused by high temperature chlorination in the commercial Ti extraction process; and the recycling of Ti from a low grade Ti-waste. |
