ALDEX Weak Acid Cation Series
WAC Weak Acid Cation Resin
Aldex WAC is a premium-grade, weak acid gel-type, cation resin supplied in the hydrogen form as moist, tough, uniform spherical beads. Ion exchange activity is based on its carboxylic functional group. Aldex WAC is intended for use in dealkalization, deionization, and chemical processing applications.
Aldex WAC Technical Bulletin: English (PDF)
Aldex WAC Safety Data Sheets: English (PDF)
Physical Chemical Properties
| Polymer Structure: | Acrylic / divinylbenzene copolymer |
| Functional Group | R-(COOH)- |
| Ionic Form as Shipped: | Hydrogen |
| Physical Form: | Tough, spherical beads |
| Screen Size Distribution: +16 mesh -40 mesh | 16 to 40 mesh Less than 5% Less than 2% |
| pH Range: | 0 to 14 |
| Moisture Content: | 53 to 58% |
| Solubility: | Insoluble |
| Shipping Weight: | 47 lbs per cubic foot |
| Swelling H+ to Na+: | 90% maximum |
| Total Capacity: | 4.2 meq/ml minimum |
| Sphericity: | 90+% |
Recommended Operating Conditions
| Maximum Temperature: | 165ºF (75ºC) |
| Bed Depth: | 30” minimum |
| Service Flow Rate: | 2 to 5 US GPM per cubic foot |
| Backwash Flow Rate: | 50 to 75% bed expansion |
| Regenerant Strength*: Hydrochloric Acid Sulfuric Acid | 3 to 6% 0.5 to 0.8% |
| Regenerant Flow Rate: | 0.3 to 0.75 US GPM per cubic foot |
| Regenerant Contact Time: | 30 minutes minimum |
| Regenerant Dosage Level: | Depends on alkalinity |
| Displacement Rinse | 0.3 to 0.75 US GPM per cubic foot |
| Displacement Rinse Volume: | 10 to 15 gallons per cubic foot |
| Fast Rinse Rate: | 2 to 5 US GPM per cubic foot |
| Fast Rinse Volume: | 35 to 60 gallons per cubic foot |
*Caution: Do not mix ion exchange resins with strong oxidizing agents. Nitric acid and other strong oxidizing agents can cause explosive reactions when mixed with organic materials, such as ion exchange resins.
WAC Features
Carboxylic Functional Groups
Give extremely high regeneration efficiencies and high operating capacities.
Uniform Particle Size
95% of all beads are in the minus 16 to plus 40 mesh range; giving a lower pressure drop while maintaining the superior kinetics of standard mesh size products.
Superior Physical Stability
90% plus sphericity and high crush strengths together with a very uniform particle size provide greater resistance to bead breakages and maintaining low pressure drops.
Low Swelling
Less than 90% on complete exhaustion to the sodium form.
Safety Information
A material safety data sheet is available for Aldex WAC. Copies can be obtained from Aldex Chemical Co., LTD. Aldex WAC is not a hazardous product and is not WHMIS controlled.
Caution: Acidic and basic regenerant solutions are corrosive and should be handled in a manner that will prevent eye and skin contact. Before using strong oxidizing agents in contact with ion exchange resin, consult sources knowledgeable in the handling of these materials.
Pressure Drop
The graph below (Fig 1.) shows the expected pressure loss per foot of bed depth as a function of flow rate, at various water temperatures.
Fig. 1 Pressure Drop vs Flow Rate at various degrees Fahrenheit (F°)
Backwash Characteristics
After each cycle, the resin bed should be backwashed at a rate that expands the bed 50 to 75 percent. This will remove any foreign matter and reclassify the bed. (Fig 2.)
Fig. 2 Expansion vs Flow Rate at various degrees Fahrenheit (F°)
Applications
Demineralization
Aldex WAC can be used to remove cations associated with alkalinity in multiple bed demineralizers.
Softening
In certain applications, Aldex WAC can be operated as a softener in the sodium cycle. This requires a two-stage regeneration using a strong acid first stage to remove multivalent ions from the bed followed by a neutralization rinse with an alkali.
Dealkalization
Bicarbonate alkalinity can be effectively removed using Aldex WAC in the hydrogen form.
Operating Capacity
