Preparation of nanosized γ-Al2O3 from coal gangue

This paper reports the preparation of nanosized #x03B3;-Al
2
O
3
from coal gangue. The process consist of five stages: calcined coal gangue to prepare metakaolin, alkaline-leaching and alkaline-fusion the metakaolin, preparation of #x03B3;-AO(OH), and #x03B3;-AO(OH) transferred to #x03B3;-Al
2
O
3
with high temperature heat treatment. The samples were characterized by different scanning calorimetries and thermogravimetry (DSC-TGA), X-ray diffractometer (XRD), X-ray fluorescence spectrometer (XRF) Scanning electron microscopy (SEM) and BET surface area measurements. The results indicated that the prepared #x03B3;-Al
2
O
3
were lightweight, non-crystallinne structure, white porous solids. The particle size is about 20–50 nm, #x03B3;-Al
2
O
3
particles and particles form a three-dimensional network structure, the diameters of the pores inside the particles are between 2 and 10 nm.