Innovative vacuum distillation technology for preparing refined Al from Al-Mg alloy

Area of Science:

• Metallurgical Engineering
• Materials Science

Background:

• Aluminum (Al) purification from Al-Mg alloys is critical for various industrial applications.
• Existing purification methods may face limitations in efficiency and environmental impact.

Purpose of the Study:

• To develop and validate an advanced vacuum distillation (VD) approach for high-purity Al production from Al-Mg alloys.
• To establish a quantitative basis for assessing Al purification limits using vapor-liquid equilibrium (VLE) data.

Main Methods:

• Activity coefficients of Al-Mg binary alloy components were calculated using Molecular Interaction Volume Model (MIVM), Non-Random Two-Liquid (NRTL) model, and Wilson equation.
• The NRTL model was selected for its accuracy and used to generate a VLE diagram for Al-Mg alloys between 973-1373 K.
• Kilogram-scale VD experiments were conducted at 1373 K for 120 minutes to verify theoretical predictions.

Main Results:

• The NRTL model accurately predicted activity coefficients, enabling the creation of a precise VLE diagram.
• Vacuum distillation demonstrated rapid and efficient Al purification, achieving 99.9989% purity.
• A high direct recovery efficiency of 97.98% was obtained in experimental verification.

Conclusions:

• Vacuum distillation is a highly effective and rapid method for purifying Al from Al-Mg alloys.
• The developed VLE diagram provides a reliable tool for optimizing the VD process.
• The VD process is environmentally sustainable, producing no gaseous emissions or effluents, aligning with green metallurgy principles.