Duolite A568

Summary

Product identification

Duolite™ A568 Ion Exchange Resin is a food-grade, weak base anion exchange resin based on crosslinked phenol-formaldehyde polycondensate.

Applications

• Starch hydrolysates (e.g., glucose isomerase immobilization for enriched fructose syrups, beta-amylase immobilization for high maltose syrup production).
• Fat processing (e.g., lipase immobilization for glyceride interesterification and hydrolysis, esterification of fatty acids).

Typical Properties

Physical Properties

• Copolymer: Crosslinked phenol-formaldehyde polycondensate
• Matrix: Porous
• Type: Weak base anion
• Functional Group: Tertiary amine
• Physical Form: Green-gray, opaque, granules
• Total Pore Volume: 0.78 – 1 mL/g
• Average Pore Diameter: 300 – 500 Å

Chemical Properties

• Ionic Form as Shipped: Free base (FB)
• Total Exchange Capacity: ≥ 1.20 eq/L
• Water Retention Capacity:
  • Fully Hydrated: 62 – 67%
  • As Delivered: 5.5 – 10.5%

Particle Size

• ≤ 150 µm: ≤ 0.2%

• 850 µm: ≤ 2.0%

Stability

• Swelling (OH⁻ → Cl⁻): 7%

Density

• Particle Density: 1.10 – 1.14 g/mL
• Shipping Weight: 307 g/L

Suggested Operating Conditions

• Maximum Operating Temperature: 65°C (149°F)
• Bed Depth, min.: 2000 mm (6.6 ft)
• Flowrate: ≤ 5 BV*/h
• Pressure Drop: ≤ 2.5 bar (35.3 psi) across each column
  • 1 BV (Bed Volume) = 1 m³ solution per m³ resin or 7.5 gal solution per ft³ resin

Hydraulic Characteristics

• Bed expansion: Approximately 60% at 4 m/h (1.6 gpm/ft²) with water at 20°C (68°F).
• Pressure drop: Approximately 0.06 bar per m/h linear velocity (2.1 psi per gpm/ft²) with water at 20°C (68°F).

Application Information

Immobilization Procedures

Two general procedures are described:

1. Column operation: Involves dissolving the enzyme, adjusting the pH of the resin, recirculating the enzyme solution through the column until adsorbed, and then backwashing.
2. Batch operation: Involves dissolving the enzyme, equilibrating the resin slurry with buffer, adding the enzyme solution to the slurry with stirring until adsorbed, and then decanting with deionized water.

Enzymatic Reaction Conditions

Enzymatic reactions are typically carried out in down-flow columns. Multiple columns may operate in series or parallel to ensure constant enzymatic conversion. Flowrate is determined by desired conversion levels and pressure drop.

Note: Duolite™ A568 Ion Exchange Resin is supplied partially dried. Volume is measured in the fully hydrated form after exhaustion, regeneration, backwashing, settling, and draining.

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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