Abstract: In order to solve the problems such as uneven distribution of pore size,over-large crystal particles and many impurities caused by batch operation in traditional batch carbonation decomposition process,a new technology combining high-gravity technology with continuous carbonization process is proposed for preparing pseudo-boehmite and γ-Al2O3.Pseudo-boehmite is prepared by cross-flow rotating packed bed with CO2 and NaAlO2 as raw materials.The impacts of the concentration of NaAlO2 solution,gas-liquid ratio and high-gravity factor on the pore properties of pseudo-boehmite are investigated.Macro-porous γ-Al2O3 is prepared through reaming modification and calcination of pseudo-boehmite.With the increases of the concentration of NaAlO2 solution,gas-liquid ratio and high-gravity factor,the specific surface area and pore volume of pseudo-boehmite increase firstly and decrease then.The optimal preparation conditions are as follows:the concentration of NaAlO2 solution is 0.1 mol·L-1,the gas-liquid ratio is 3:1 and the high-gravity factor is 54.The nanometer macro-porous fibrous γ-Al2O3 with specific surface area and pore volume of 322 m2·g-1 and 1.826 ccl·g-1 respectively is obtained after reaming modification and calcination.The results show that the product obtained by the high-gravity continuous carbonation decomposition method exhibits high purity,uniform pore size distribution and high production efficiency,which is suitable for industrial amplification.
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