Study on the Extraction of Aluminum From Aluminum Dross Using Alkali Roasting and Subsequent Synthesis of Mesoporous γ-Alumina

This study presents a process for recovering aluminum from aluminum dross (an industrial waste product) via an alkali roasting process and using it to synthesize mesoporous gamma-alumina. The results show that the inherent chlorides in dross (KCl and NaCl) reduce Al extraction efficiency and should be removed first by water leaching. Use of salt-free dross increases the Al extraction rate (from 85 to 96 pct) within 90 minutes alkali roasting at 923 K (650 A degrees C). In addition, an ammonium bicarbonate byproduct can be obtained from water leaching due to the hydrolysis of AlN, which can be used as a precipitating agent in the boehmite sol preparation. Synthesis of mesoporous gamma-alumina was carried out by the sol-gel method with EO20PO70EO20 (P123) as a template. The prepared mesoporous gamma-alumina was characterized as having a disordered mesostructure with a high pore volume of 1.02 cm(3)/g and surface area of 312 m(2)/g. Thus, we achieved highly efficient utilization of aluminum dross and yielded products with high added value. Mesoporous gamma-alumina has potential applications in environmental remediation and catalysis.