Relationship between Chemical Structure of Caking Additives Produced from Low Rank Coals and Coke Strength

摘要

Coke strength can be enhanced by adding HyperCoals (HPC). HPC can be produced from different rank of coals including low rank coals. The aim of this study is to investigate and evaluate the usability of HPC from low rank coals as caking additive. ~(1)H-NMR, solid state ~(13)C-NMR, and elemental analysis were carried out to investigate the molecular structure of HPC prepared from low rank coals. The results showed that the number of aromatic rings in unit structure increased from 1-2 in original coals to 2-3 in HPCs extracted at 633 K. Effect of extraction temperature was also investigated and it was found that ratio of 3 aromatic rings increased in HPC extracted at 673 K, in comparison to HPC extracted at 633 K. The strength of cokes produced by adding HPC was directly a function of number of aromatic rings in the HPC and increased with increasing number of rings.