Abstract

In this paper, factors affecting the microwave drying characteristics of rutile TiO₂ were discussed, and the data were fitted with nine common thin layers drying kinetic models. The results demonstrate that the drying efficiency of rutile TiO₂ shows a positive relationship with microwave power. With a microwave power increase from 320W to 640W, the drying time is shortened by 35.7%. The microwave drying efficiency presents a positive relationship with initial moisture content. With a moisture content increase from 2% to 12%, the average drying rate increased from 0.009% · s⁻¹ to 0.054% · s⁻¹. Additionally, the microwave drying efficiency is positively correlated with the initial mass when the initial mass is below 45 g. Otherwise, the microwave drying efficiency is negatively correlated with the initial mass. Besides, kinetic models were used to understand the microwave drying process of nature rutile TiO₂. The results show that the Modified Page model agrees well with the experimental data, and the fitting parameters are consistent with the law of matching degree. The demonstration of microwave drying techniques can be applied effectively and efficiently to the treatment processing of drying of the raw materials of metallurgy and chemical industry with the theoretical and scientific basis.