Preparation of nanoscale alumina powder by heterogeneous azeotropic distillation processing

Nanoscale alumina powders were successfully prepared by an improved sol-gel method. Effects of different drying methods on prepared grain properties were studied. The results show that heterogeneous azeotropic distillation processing can dehydrate effectively during gel drying, and prevent the formations of agglomeration. The products were identified by TEM, XRD, BET, TG and DTA. Al2O3 powders with nanoscale sizes (about 68nm), homogeneous disperse, better sphere and low impurity content were obtained, meanwhile, the dried gel powders can be converted to alpha -phase completely at lower temperature (1150 degreesC) and shorter time (30 min).