Swelling kinetics of several residues from Shenhua coal extraction

In order to understand the mechanism of swelling and the relation between swelling behavior and solvent extraction,the swelling kinetics of residues from Shenhua coal extracted by CS2/NMP with different mixing ratios were studied in different solvents.The result shows that the swelling rates of extraction residues increase along with swelling temperature.The swelling rate in polar solvent NMP is much higher than that in non-polar solvent THN.Solvent extraction has a great effect on the swelling of extraction residues.The swelling activation energy of extraction residues increases and the swelling rate decreases with the increase of extraction yield.The swelling activation energies of extraction residues in NMP and THN are less than 10 kJ/mol,suggesting that the swelling process is controlled by solvent molecular diffusion in coal structure.