PREPARATION OF ALUMINA FROM RETORTING RESIDUE OF OIL SHALE

In this research, the leaching and preparation of Al2O3 from retorting residue of Fushun east open-pit oil shale in China were investigated. The optimum acid leaching conditions are the following: activation temperature is 850 oC, activation time is 1h, the particle size of the raw material is 0.074mm, the concentration of acid is 12%, the liquid to solid ratio is 5:1, reaction temperature is 100 oC and reaction period is 1.5 h. The homogeneous chemical precipitation method was applied for the preparation of alumina. Optimum conditions for alumina preparation were determined and are as follows: reaction at 55 oC for 1.5 h, the concentration of sodium meta aluminate is 0.4 mol/L, the dose of surfactant is 0.3%. The product can be effectively purified by washing with 25% acetic acid, and then characterized by laser particle size distribution, X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results prove that the product is γAl2O3 with particle diameters in the range of 0.6–0.9 μm, and its degree of purity is 98.7%.