AmberLyst A21

Summary

Product Identification

• Product Name: AMBERLYST™ A21 Ion Exchange Resin
• Type: Industrial-grade, Weakly Basic Polymeric Resin
• Copolymer: Styrene-divinylbenzene
• Matrix: Macroporous
• Functional Group: Tertiary amine
• Physical Form: Beige, opaque, spherical beads
• Ionic Form as Shipped: Free base (FB)

Description & Applications

AMBERLYST™ A21 is a weak base anion exchange resin designed for removing acidic materials from product streams, particularly those with a pKa > 4.75. It is also used for adsorbing SO₂ from gas streams.

• Deacidification
• Phenol removal from benzene
• Inhibitor removal from monomers (hydroquinone (HQ), hydroquinone monomethyl ether (MEHQ), tertiary butyl catechol (TBC))
• Base-catalyzed reactions

Typical Properties

Physical Properties

• Water Retention Capacity: 56 – 62%
• Particle Size:
  • Particle Diameter: 490 – 690 µm
  • Uniformity Coefficient: ≤ 1.80
  • Finer than 300 µm: ≤ 1.0%
  • Larger than 1180 µm: ≤ 2.0%
• Swelling (in solvent):
  • Phenol: 77%
• Density:
  • Shipping Weight: 660 g/L
• Pore Structure:
  • Nitrogen BET Surface Area: 35 m²/g
  • Total Pore Volume: 0.10 cc/g
  • Average Pore Diameter: 110 Å

Chemical Properties

• Total Exchange Capacity (on a water-wet basis): ≥ 1.30 eq/L
• Dry Weight Capacity: ≥ 4.60 eq/kg
• Concentration of Base Sites: ≥ 4.60 eq/kg

Suggested Operating Conditions

• Maximum Operating Temperature: 100°C (210°F)
• Bed Depth, min.: 600 mm (2.0 ft)
• Pressure Drop, max.: 1 bar (15 psig) across the bed
• Flowrates:
  • Operating: 1 – 5 BV/h (0.125 – 0.625 gpm/ft³)
  • Linear Hourly Space Velocity (LHSV): 0.5 – 5 h⁻¹
  • Backwash: See Figure 1 in the official PDF.
  • Regeneration: 2 – 8 BV/h (0.25 – 1 gpm/ft³)
• Regenerants & Concentrations:
  • NaOH: 2 – 4%
  • NH₄OH: 2 – 4%
  • Na₂CO₃: 4 – 8%
• Regenerant Level: 120% of ionic load for all listed regenerants.
• Contact Time:
  • Regeneration: ≥ 30 minutes
• Rinse:
  • Slow Rinse: Regeneration flowrate for 2 BV (15 gal/ft³)
  • Fast Rinse: Operating flowrate for 2 – 4 BV (15 – 30 gal/ft³)

Hydraulic Characteristics

• Estimated bed expansion as a function of backwash flowrate and temperature is shown in Figure 1 of the official PDF.
• Estimated pressure drop as a function of service flowrate and temperature is shown in Figure 2 of the official PDF. These estimates are valid at the start of a service run with clean water and a well-classified bed.

Disclaimer: This data 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