| Oil shale that was called as liquid fuel was produced as fuel and other industry materials. Oil shale often generated much more ashs after dry distillation and burning. Generally, the ashs were used to fill the mine entrance, prepare the building materials such as cement, building block, light ceramisite and so on. But the disposal amount was limit, it is necessary to find the right solution to avoid the environment pollution. The oil shale ash was composed of inorganic elements such as alumina and silca that exceed 60% and were extracted to produce chemical manufactures. Every year there were a lot of ashs in our country and the ashs were prepared chemical products and improved the addition value. So, to effectively utilize oil shale ash (OSA) becomes an important issue.In the paper, kinds of oil shale and ash of physical chemical characteristics from different areas were researched. The two kinds of oil shale ashs were chosen and compared the difference of mineral and chemical elements, and made sure of the extraction technology.The I kind of oil shale ash contains kaolinite and quartz and can prepare the alumina and silca by high temperature calcination and hydrometallurgy technology. Box-Behnken statistical design was used to optimize the factors affecting the efficiency and investigate the prominence of the factors. The cubic photograph was obtained to the optimum conditions and the model was validated in the actual experiments. The alumina extraction efficiency reached 89.21% and the silica efficiency reached 73±0.50% and was close to 73.39%. It was showed that Box-Behnken statistical design expert was suitable to optimum the condition. At the optimum condition of reaction time 5 h, reaction temperature 100℃, and the concentration of sodium hydroxide 40 wt.%, the extraction silica efficiency reached 73±0.50%. The optimal alumina extraction condition was:reaction time 4h, reaction temperature 100℃, sulfuric concentration 50 wt.%. The maximum efficiency reached 89.17%. TheⅡkind of oil shale ash was composition of alkali feldspar and plagioclase. It is difficult to use the hydrometallurgy technology to extract alumina and silica. With sodium carbonate as an auxiliary agent, a sodium aluminate liquor with much impurity such as Fe, Ca, Mg was purified by adjusting the pH value and obtained the products. The ashes after acid reaction were prepared silica and discussed the affecting factor:reaction time, NaOH concentration, reaction temperature.The alumina and silica prepared in the experiments were characterized by several characterization methods. The results indicated that the preparedγ-Al2O3 is irregular in shape with granular size ranged to 2-15μm. The BET specific surface of alumina was investigated. The nitrogen adsorption-desorption isotherm are shown and the isotherm obtained for the sample was of type IV. The microstructure analysis showed that the shape of silica white is sphere with different sizes. The IR spectra was in agreement with the standard card. The TEM micrograph showed that the particles aggregated and were inhomogeneous in size and shape. The products prepared from the two kinds of oil shale ashs were accorded with the standard and the technologies were feasible.
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