Effect of Sulfuric Acid Corrosion on Flotation Performance of Calcite by Changing Surface Roughness

Area of Science:

• Mineral Processing
• Surface Chemistry
• Materials Science

Background:

• Surface roughness critically influences mineral flotation efficiency.
• Understanding mineral surface alterations is key to optimizing separation processes.

Purpose of the Study:

• To investigate the impact of sulfuric acid corrosion on calcite surface roughness.
• To analyze the subsequent effects on calcite flotation performance.

Main Methods:

• Microflotation tests were conducted to assess floatability.
• Surface morphology and roughness were analyzed using Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) and Atomic Force Microscopy (AFM).
• Surface chemistry was characterized by Fourier Transform Infrared (FT-IR) spectroscopy and contact angle measurements.

Main Results:

• Sulfuric acid treatment severely diminished calcite floatability, with recovery dropping below 19% at a 4 mL (3 mol/L) dosage.
• SEM-EDS and AFM revealed significant changes in surface morphology, decreased average surface roughness, and reduced surface area.
• FT-IR and contact angle analyses indicated enhanced surface hydrophilicity and decreased sodium oleate adsorption.

Conclusions:

• Sulfuric acid corrosion negatively impacts calcite flotation by reducing surface roughness and hydrophobicity.
• Altered surface morphology and chemistry, including reduced active Ca2+ sites, explain the diminished flotation performance.