Qiang Gao,Hongyun Hu,Chan Zou,Yang Hu,Huan Liu,Xian Li,Hong Yao
Molten salt thermal treatment of solid waste is a promising way for energy recovery and pollutant removal. However, the migration of nitrogen during pyrolysis of waste tires poses a challenge for cleaner production. This study investigated nitrogen conversion pathways during waste tires pyrolysis using a binary NaOH-Na 2 CO 3 salt at 425, 500, and 575 °C. The results demonstrated that amine-N and pyrrole-N were the main N-containing species in waste tires. Compared to conventional pyrolysis, the molten salt enhanced the deamination of the amine-N while increasing levels of NH 3 and aniline. Owing to the catalytic benefits of molten salt, the C-N bond cleavage of amine-N was initiated by electron transfer involving the combination of NH 2 -Phenyl structures with Na + . The hydrocracking of Phenyl-NH-Phenyl in amine-N was facilitated by the available H radicals (or H 2 ). Furthermore, molten salt obstructed the contact of C(N) sites on the char surface, causing the suppression of HCN production. The SH radicals might be consumed by OH – ions, which disabled the formation path of benzothiazole from aniline and SH radicals. Comparatively, pyrrole-N showed limited reactivity and remained in char. This work contributes to nitrogen regulation during the molten salt treatment of solid waste.
A series of nitrogen doped biomass carbon catalysts were prepared through two different nitrogen doped methods by using soybean meal as the raw material, melamine as nitrogen source and KOH as the activators. The catalysts were characterized by BET, SEM , CO 2 -TPD, EA , FTIR , XPS and Raman. The catalytic performances of CH 4 –CO 2 reforming over different samples were also studied. The results show that the preparation method of the catalyst significantly affects the structural characteristics, N content and N species type of the catalyst. The characterization results also show the proportion of pyrrolic-N in the catalyst prepared by in-situ nitrogen doped method (Y-NC) is higher than that in prepared by the post-treatment method (H-NC). Pyrrole-N is more conducive to the adsorption and activation of CO 2 . So, the catalyst prepared by in-situ nitrogen doped method has good catalytic activity and stability. The conversion of CH 4 and CO 2 were respectively 40% and 65% at 900 °C after 50 h of CH 4 –CO 2 reforming reaction .
危险品化学品经营许可证（带存储）