Preparation of carbon nanomaterials using two-group arc discharge plasma

[Display omitted] •A new preparation method of carbon materials based on two groups of plasma was achieved.•One combination of AC arc plasma and DC arc plasma was adopted.•One combination of non-thermal plasma and thermal plasma was adopted.•Optimal operation parameters and CB generation mechanism were determined.•A technical process combined a fluidized bed with plasma system was designed. Carbon nanomaterials were prepared using two-group arc discharge plasma method in this study. A combination of an alternating current (AC) arc discharge plasma and a direct current (DC) arc discharge plasma in a fluidized bed was used, in which propane was cracked into carbon blacks (CB) with controlled structure and hydrogen. The effects of parameters such as electrode type, frequency of AC arc discharge, current of DC arc discharge and gas flow ratio (propane/argon) on the synthesis and properties of CB were investigated. A systematic study of the size, morphology, microstructure and surface chemical composition of CB was conducted using various characterization techniques. By using this process, spherical and hydrophobic CB with a narrow size distribution, high degree of graphitization and large specific surface area were produced under optimal experimental conditions. Then, as-prepared CB were used to adsorb heavy-metal ions in water and to reinforce the engineering plastic. The results verified that the adsorption rate of the Cr (VI) ion was increased significantly and that the CB enhanced the electrical and mechanical properties of acrylonitrile–butadiene–styrene (ABS)/natural rubber (NR) composites.