Liquid dispersion in an external-loop airlift slurry reactor was experimentally studied. The effects of the superficial gas velocity, concentration of fine particle, flowing resistance, and liquid level in the gas-liquid separator on the liquid dispersion coefficient were investigated. A liquid dispersion model was proposed based on Taylor dispersion equation to predict the liquid dispersion coefficient. According to this model, the dispersion coefficient and the combination factor u(L)(2)epsilon(L) have a linear relationship. Validation of the liquid dispersion model together with the hydrodynamic model in our previous work was made by comparing the experimental and predicted results. The good agreement showed that the models could predict the liquid dispersion coefficient and the hydrodynamic behaviors of an airlift slurry reactor in a wide range of operating conditions with a satisfactory accuracy. (C) 2007 Elsevier B.V. All rights reserved.