Extraction and characterization of alumina nanopowders from aluminum dross by acid dissolution process

Abstract

A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was extracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Aluminum dross samples were found to approximately contain 75wt% Al₂O₃ and 12wt% SiO₂. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extraction of alumina were studied to optimize the dissolution process. First, Al(OH)₃ was produced in the form of a gel. Calcination of the Al(OH)₃ gel at 1000°C, 1200°C, and 1400°C for 2 h produced γ-Al₂O₃, (α+γ)-Al₂O₃, and α-alumina powder, respectively. Thermal characterization of the Al(OH)₃ gel was performed by thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calorimetry (DSC). The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence (XRF) spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.

Keywords

aluminum dross / alumina / nanoparticles / acid dissolution / calcination / X-ray fluorescence analysis

References

[1] Rogojan R, Andronescu E, Ghiţulică C, Vasile BS. Synthesis and characterization of alumina nano-powder obtained by sol-gel method. UPB Sci. Bull. B, 2011, 73(2): 67.

[2] Cordingley R, Kohan L, Ben-Nissan B, Pezzoti G. Alumina as an orthopaedic biomaterial: characteristics, properties, performance and applications. J. Australas. Ceram. Soc., 2003, 39(1): 20.

[3] Yoon TR, Rowe SM, Jung ST, Seon KJ, Maloney WJ. Osteolysis in association with a total hip arthroplasty with ceramic bearing surfaces. J. Bone Joint Surg. Am., 1998, 80(10): 1459.

[4] Thamaraiselvi TV, Rajeswari S. Biological evaluation of bioceramic materials: a review. Trends Biomater. Artif. Organs, 2004, 18(1): 9.

[5] A. Adamson, E. Bloore, and A. Carr, Essential Readings in Light Metals, Alumina and Bauxite, Edited by D. Donaldson and B.E. Raahauge, WILEY, Hoboken, New Jersey, 2013, p.100.

[6] W.H. Tingle, J. Petit, and W.B. Frank, Handbook of Extractive Metallurgy, Edited by F. Habashi, WILEY-VCH, Weinheim, Germany, 1997, p. 1039.

[7] Kelmers AD, Canon RM, Egan BZ. Chemistry of the direct acid leach, calsinter, and pressure digestion-acid leach methods for the recovery of alumina from flyash. Resour. Conserv., 1982, 9, 271.

[8] David E, Kopac J. Aluminum recovery as a product with high added value using aluminum hazardous waste. J. Hazard. Mater., 2013, 261, 316.

[9] Panias D, Skoufadis C, Paspaliaris I. The boehmite process: an innovative variation of the Bayer process. Proceedings of EMC, Friedrichshafen, 2001 371.

[10] Dash B, Das BR, Tripathy BC, Bhattacharya IN, Das SC. Acid dissolution of alumina from waste aluminium dross. Hydrometallurgy, 2008, 92(1–2): 48.

[11] Peters FA, Johnson PW, Kirby RC. Methods for producing alumina from clay: an evaluation of five hydrochloric acid process. Investigation Report of U.S. Bureau of Mines, 1962 68.

[12] Phillips CV, Wills KJ. A laboratory study of the extraction of alumina of smelter grade from China clay micaceous residues by a nitric acid route. Hydrometallurgy, 1982, 9(1): 15.

[13] Mahi P, Bailey NT. The use of coal spoils as feed materials for alumina recovery by acid-leaching routes: 4. The extraction of iron from aluminiferous solutions with amines, in particular alamine 336. Hydrometallurgy, 1985, 13(3): 293.

[14] Peters FA, Johnson PW. Revised and Updated Cost Estimates for Producing Alumina from Domestic Raw Materials, 1974, Wahington DC, Information Circular (8648), U.S. Department of the Interior

[15] Sultana UK, Gulshan F, Gafur MA, Kurny AWS. Kinetics of recovery of alumina from aluminium casting waste through fusion with sodium hydroxide. Am. J. Mater. Eng. Technol., 2013, 1(3): 30.

[16] Rahaman MA, Gafur MA, Kurny ASW. Kinetics of recovery of alumina from coal fly ash through fusion with sodium hydroxide. Am. J. Mater. Eng. Technol., 2013, 1(3): 54.

[17] Cullity BD. Elements of X-Ray Diffraction, 1978 398.

[18] Al-Zahrani AA, Abdul-Majid MH. Extraction of alumina from local clays by hydrochloric acid process. JKAU Eng. Sci., 2009, 20(2): 29.

[19] Eisele JA, Bauer DJ, Shanks DE. Bench-scale studies to recover alumina from clay by a hydrochloric acid process. Ind. Eng. Chem. Prod. Res. Dev, 1983, 22(1): 105.