High purity amorphous alumina nanoparticles from hazardous aluminum dross

This work presents synthesis and characterization of high purity amorphous alumina (a-Al2O3) from hazardous aluminum dross (HAD). The a-Al2O3 was prepared through a hydrometallurgical process including acid leaching of the HAD, co-precipitation of the obtained leachate, and re-dissolution of precipitated metal hydroxides in caustic soda solution. At first, aluminum hydroxide gel was precipitated from sodium aluminate filtrate after adding hydrochloric acid. Finally, to prepare alumina, the aluminum hydroxide gel was calcined at 550 °C for 2 h. The as-prepared alumina was characterized using X-ray diffractometry (XRD), X-ray fluorescence (XRF) analysis, and transmission electron microscopy (TEM). The XRD pattern revealed no crystalline phases, confirming the amorphous nature of the material. The XRF analysis showed a high purity of more than 98%. The TEM micrograph clearly disclosed that the as-prepared alumina contains agglomerated flake-like nanoparticles. Overall, the results propose a promising solution to the environmental concerns of the waste, as well as gaining economic benefits.

High purity amorphous alumina nanoparticles from hazardous aluminum dross Keywords:

Amorphous , Alumina , Dross , Aluminum hydroxide , Hazardous