LEWATIT® S 4428

Summary

Product identification

Lewatit® S 4428 is a food-grade, macroporous anion exchange resin of medium basicity. It is based on polystyrene with tertiary and a low level of quaternary amino groups, and is bead-shaped with a special bead size distribution.

It is suitable for:

• Removal of acid and simultaneous decolorization of solutions of organic products (e.g., glucose, other sugars).
• Use in Lewatit® WS system (fluidized bed).
• Use in Lewatit® VWS system (compound fluidized bed).
• Use in standard co-current regenerated systems.

Physical and Chemical Properties

• Ionic form as shipped: free base/Cl⁻
• Functional group: tertiary/quaternary amine
• Matrix: crosslinked polystyrene
• Structure: macroporous
• Appearance: beige, opaque
• Uniformity Coefficient: max. 1.6
• Bead size: > 90 % between 0.4 - 1.2 mm
• Effective size: 0.55 (+/- 0.05) mm
• Bulk density: 640 g/l (+/- 5 %)
• Density: approx. 1.02 g/ml
• Water retention: 52 - 58 wt. %
• Total capacity: min. 1.6 eq/l
• Volume change (free base → Cl⁻ / SO₄²⁻): max. 28 vol. %
• Volume change (total swelling, delivered → Cl⁻): typical 20 vol. %
• Stability at pH-range: 0 - 14
• Storability: max. 2 years
• Storability temperature range: -20 - 40 °C

Recommended Operating Conditions

• Operating temperature: max. 70 °C
• Operating pH-range: 0 - 8
• Bed depth: min. 800 mm
• Specific pressure drop (15 °C): approx. 1.1 kPa*h/m²
• Pressure drop: max. 250 kPa
• Linear velocity operation: max. 5-15 m/h
• Linear velocity backwash (20 °C): approx. 3-4 m/h
• Bed expansion (20 °C, per m/h): approx. 25 vol. %
• Freeboard backwash (extern/intern): 80 - 100 vol. %

Regeneration (NaOH):

• Counter current regeneration level: approx. 50 - 80 g/l
• Counter current regeneration concentration: 2 - 4 wt. %
• Co current regeneration level: approx. 50 - 80 g/l
• Co current regeneration concentration: approx. 2 - 4 wt. %
• Linear velocity regeneration: approx. 5 m/h
• Linear velocity rinsing: approx. 5 - 8 m/h
• Rinse water requirement (slow/fast): approx. 6 BV

Additional Information & Regulations

• Safety precautions: Strong oxidants can cause violent reactions. Observe the safety data sheet.
• Disposal: Dispose according to European waste nomenclature.
• Storage: Store above freezing point, dry, protected from sunlight. If frozen, thaw gradually at ambient temperature.

Disclaimer: This extraction may miss figures, footnotes, or revisions; contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror