A Novel Approach for Preparing Sepiolite Micron Powder Based on Steam Pressure Changes

Area of Science:

• Materials Science
• Mineral Processing

Background:

• Mechanical extrusion for sepiolite micronization often damages fiber structure and fails to disperse bundles effectively.
• Preserving the microstructure of sepiolite is crucial for its functional properties.

Purpose of the Study:

• To develop a new micronization method for sepiolite using steam pressure changes.
• To investigate the impact of steam pressure on sepiolite's particle size, microstructure, and properties.
• To compare the steam pressure method with traditional mechanical extrusion.

Main Methods:

• Micronization of sepiolite using controlled steam pressure changes.
• Characterization using X-ray fluorescence spectrometer (XRF), X-ray diffractometer (XRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis.
• Evaluation of particle size distribution, crystalline structure integrity, and specific surface area.

Main Results:

• Sepiolite particle size is highly dependent on steam pressure, yielding a D97 of 21.27 μm at 0.6 MPa.
• The steam pressure method preserves the crystalline structure integrity of sepiolite fibers, unlike mechanical extrusion.
• Specific surface area increased from 80.15 m² g⁻¹ to 141.63 m² g⁻¹ with increasing steam pressure (0.1 to 0.6 MPa), a 1.6-fold improvement over mechanical extrusion.

Conclusions:

• Steam pressure treatment is a superior method for sepiolite micronization, effectively dispersing bundles while maintaining structural integrity.
• This method significantly enhances the specific surface area of sepiolite, offering improved material properties.
• The findings provide a foundation for optimizing sepiolite processing for advanced applications.