A Method for Preparing Macroporous Activated γ-Al2O3

摘要

Alumina with low apparent density was prepared by continuous concurrent gelation precess with aluminum sulfate [A12(SO4)3] and sodium hydroxide (NaOH) as raw materials.XRD, TEM, nitrogen adsorption-desorption,mercury porosimetry, and TG-DSC were employed to characterize crystal phase, morphology, soecific surface area, and pore size diatrbution of the prepared samples.Influences of reaction pH, OH-concentration, and reaction time on apparent density and surface area were discussed.Results showde the better preparation conditions were:Al3+ concentration of 0.5mol/L, OH-concentration of 1.2mol/L, gelation pH of 9, reaction tempetature of 65°C, neutralization reaction time of 60 min and aging time of 120min.Under those conditions,the obtained alumina carriers exhibited the charecteristics of having apparent density not less than 0.32g/ml, surface areas not more than 200m2/g, and total pore volume not less than 1.2mL/g.In addition, pore volume of the pore whose pore radius greater than 100nm accounted for over 50％ of the total pore volume.