Iranian Chemical Engineering Journal

Iranian Chemical Engineering Journal

Investigation of Aluminum Recycling from Urban Waste Using the Salt Flux Method

Document Type : Original Article

Authors
A. R. Peikar 1
E. Abdollahzade 1
A. R. Hemmati 2
A. Bazyari 3
1 BSc. Student of Chemical Engineering, Iran University of Science and Technology
2 Associate Professor of Chemical Engineering, Iran University of Science and Technology
3 .Assistant Professor of Chemical Engineering, Iran University of Science and Technology
10.22034/ijche.2025.487814.1460
Abstract
Recycling aluminum from urban waste is a crucial method for reducing energy consumption and preserving the environment. The extraction of aluminum from bauxite is not only costly but also generates significant environmental pollutants. In contrast, recycling aluminum through the remelting of scrap, particularly beverage cans, can reduce the need for raw material extraction while consuming up to 95% less energy. This study examines the aluminum recycling process using the salt flux method. The effects of parameters such as temperature, salt composition in the flux, mixing conditions, and scrap shape on recycling efficiency and aluminum purity were evaluated. The results showed that at 900°C, with a flux composition of 70% sodium chloride and 27% potassium chloride, in the presence of argon gas and proper mixing, the purity of the recovered aluminum reached 98.05%. Reducing the temperature to 800°C significantly lowered energy consumption while having minimal impact on the final product's purity. Additionally, compacted scrap exhibited a higher recycling yield compared to sheet-like scrap.
The findings of this study indicate that the use of salt flux not only enhances the recycling process and reduces slag formation but also presents an economical and environmentally friendly solution for industrial-scale aluminum recycling.
Keywords
Aluminum
Aluminum Recycling
Salt Flux
The Environment
Subjects
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Iranian Chemical Engineering Journal
Volume 25, Issue 144
May and June 2026
Pages 69-80