Abstract:
Coal swelling is one of the major factors causing viscosity change during direct coal liquefaction. The swelling behavior of two kinds of coal in three organic solvents at different temperatures was studied. In polar solvents, the swelling ratio of Shenhua coal was larger than that of Xinzhuang coal having a high coal rank; however, in non-polar solvent tetralin, it was smaller. A higher temperature produced a faster rate of coal swelling and a larger swelling ratio. Coal swelling ratio was found to be dependent on the solubility of coal in solvent; the more soluble coal has a larger swelling ratio.