D403
D403 is a chelating ion exchange resin bearing iminodiacetate groups [–N(CH₂COOH)₂] on the aromatic rings of a macroporous styrene-divinylbenzene copolymer. Its selectivity for metal ions resembles EDTA and exceeds that of strong or weak acid cation resins: in the presence of monovalent and divalent ions it adsorbs only divalent ions. It is used to remove Ca²⁺ and Mg²⁺ for purification of electrolytic brine, and also in wastewater treatment and recovery of precious metals.
Product Introduction
D403 is a chelating ion exchange resin bearing iminodiacetate groups [–N(CH₂COOH)₂] on the aromatic rings of a macroporous styrene-divinylbenzene copolymer. Its selectivity for metal ions resembles EDTA and exceeds that of strong or weak acid cation resins: in the presence of monovalent and divalent ions it adsorbs only divalent ions. It is used to remove Ca²⁺ and Mg²⁺ for purification of electrolytic brine, and also in wastewater treatment and recovery of precious metals.
Typical Physical & Chemical Properties
| Appearance | Light yellow to beige-gray opaque beads |
|---|---|
| Shipped form | Na+ form |
| Moisture content | 50%~62% |
| Cu chelating capacity | ≥0.6mmol/ml |
| True density (wet) | 1.10~1.20g/ml |
| Bulk density (wet) | 0.7~0.8g/ml |
| Particle size range | 0.315~1.25mm |
| Particle size range | ≥95% |
Handling, Storage & Loading Notes
- Transport & storage. Store the resin in its wet state, preferably above 0 °C. For long idle periods, keep the container closed or add brine of ≥5% NaCl. Protect from freezing during transport, and do not stack heavy objects on top of the resin to avoid crushing the beads.
- Pre-treatment. For general requirements, one alkaline → water → acid → water cycle is sufficient; for strict requirements, perform three cycles and finish with the required ionic form.
- Loading. Allow for the swelling on form conversion and leave enough freeboard to prevent overflow while keeping a proper liquid level. Keep the column aspect ratio in a reasonable range to avoid channeling. Load wet or backwash to remove air bubbles from the bed.
- Feed quality. Before entering the resin column, the liquid should be coagulated, filtered or sand-filtered to ensure it is free of suspended solids that could clog the resin pores.
- Idle columns. Resin left idle in a column for a long time must be washed out and stored clean, or kept submerged in brine; it must never dehydrate. Backwash from time to time to loosen the bed and prevent caking.