Magnesium trisilicate drying

Magnesium trisilicate drying is a critical industrial process primarily used to convert hydrated magnesium trisilicate paste or filter cake into a stable, free-flowing powder suitable for pharmaceutical (antacid formulations) and chemical applications. This dehydration step is essential for achieving desired material properties, stability, and functionality. Key Drying Technologies: Spray Drying,

 

Magnesium trisilicate drying is a critical industrial process primarily used to convert hydrated magnesium trisilicate paste or filter cake into a stable, free-flowing powder suitable for pharmaceutical (antacid formulations) and chemical applications. This dehydration step is essential for achieving desired material properties, stability, and functionality.

Purpose & Importance
Moisture Reduction:

Removes free and bound water (initially ~50–70% moisture) to achieve a residual moisture content of typically <2–5%.

Prevents caking, microbial growth, and ensures chemical stability during storage.

Functional Properties:

Converts sticky, viscous sludge into a fine, free-flowing powder with consistent bulk density.

Enhances reactivity and acid-neutralizing capacity (critical for antacids).

Processability:

Enables efficient mixing with excipients (e.g., for tablet compression) and packaging.

The Drying Process
Feed Material:

Wet filter cake or paste from precipitation synthesis (reacting magnesium salts with sodium silicate).

Key Drying Technologies:

Spray Drying:

Most efficient method for large-scale production.

Slurry is atomized into a hot-air chamber (inlet: 200–300°C; outlet: 100–120°C).

Produces hollow, spherical particles with high surface area.

Fluidized Bed Drying (FBD):

Suitable for pre-dried granules or smaller batches.

Heated air fluidizes particles at 100–150°C.

Tray/Oven Drying:

Low-cost option for small batches; slow and energy-intensive.

Material spread on trays, dried at 80–120°C with forced air.

Rotary Dryers:

Used for high-throughput continuous drying of filter cake.

Critical Parameters:

Temperature: Must exceed 100°C to remove bound water but stay below decomposition (>500°C).

Particle Size Control: Spray drying atomization pressure/nozzle design dictates powder fineness.

Moisture Monitoring: Loss on Drying (LOD) or Karl Fischer titration for precision.