Pyrolysis Routine of Organics and Parameter Optimization of Vacuum Gasification for Recovering Hazardous Waste Toner

With the rapid development of the printing industry, the amount of waste toner is increasing. Waste toner should be properly disposed because of great harmfulness and carcinogenicity to humans and the environment. For the disposal of waste toner, the previous work developed a vacuum gasification method to convert it into oils and nanoparticles with benefits of environment friendliness and low energy consumption. The properties of toner particles enable them to be transformed into high-value-added products during vacuum gasification. The vacuum gasification mechanism is further revealed in this paper. The first-order thermal dynamics shows well that the average values of apparent activation energy E and frequency factor A are 12 547.390 kJ mol(-1) and 10 148.120 min(-1), respectively. Single factor experiments show that, in the range 773-973 K, the residence time of 40 min and heating rate of 15 K min(-1) are significant and sufficient to obtain maximum oil yield, meaning the complete separation of nonmetal components from nanometal particles. Furthermore, we infer the pyrolysis pathways of acrylate-styrene copolymer at 873 K and carbon reduction reactions between carbon and Fe3O4 at 1023-1173 K and 100 Pa. This paper provides specific parameter guidance for industrial applications and mechanism analysis for efficient utilization of waste toner by the vacuum pyrolysis method.