Carbon nanotubes growth in modified bluecoke powders: Preparation and characterization, formation mechanism of CNTs, and potential application

[Display omitted] •CNTs in modified bluecoke powders were quantitatively analyzed by TG-DTG method.•Effects of Fe(NO3)3 and Fe(C5H5)2 on modified bluecoke powders were investigated.•Formation mechanisms of CNTs in the modified bluecoke powders were proposed.•Modified bluecoke powders exhibited considerable potential application. Bluecoke powders pose challenges in large-scale industrial utilization due to their small particle size and low added value that become one of primary constraints on the coking industry. In this work, Fe catalyst-assisted microwave pyrolysis of low-rank coal to prepare the modified bluecoke powders containing carbon nanotubes (CNTs) was investigated, and their potential applications were discussed. The results showed that when the addition ratios of Fe(NO3)3 and Fe(C5H5)2 were 0.05 and 0.15 respectively, the yields of CNTs in the modified bluecoke powders were 4.77 wt% and 4.15 wt%, with diameters primarily range of 50–135 nm and 30–80 nm. Additionally, the specific surface area reached 1306.29 m2/g and 643.76 m2/g. Fe(C5H5)2 significantly influenced the MBPs, and Fe and Fe3C played pivotal roles in the growth of CNTs. The excellent adsorption property and good electrochemical activity of the MBPs exhibited their considerable potential applications.