DIAION SA21A

Summary

Product Identification

DIAION SA Series - Strongly Basic Anion Exchange Resins (SBAERs). These resins possess quaternary ammonium groups (N⁺) as their functional groups, exhibiting strong basicity.

There are two types of SBAERs:

• Type I: Features trimethylammonium groups, R-N⁺(CH₃)₃. Examples include DIAION™ SA10A and SA20A, noted for highest basicity and strong anion adsorption, suitable for high-grade demineralized water.
• Type II: Features dimethylethanolammonium groups, R-N⁺(CH₃)₂·CH₂CH₂OH. These are slightly weaker in basicity than Type I, leading to potentially lower quality demineralized water but requiring fewer regenerants.

Chemistry

SBAERs can exchange anions such as Cl⁻ and SO₄²⁻. They are ion-exchangeable across the entire pH range.

Examples of ion exchange reactions:

• R-N·OH + NaCl → R-N·Cl + NaOH
• R-N·OH + HCl → R-N·Cl + H₂O

Regeneration of SBAERs is typically performed with 4% NaOH aqueous solutions, as shown in the regeneration reaction of Cl⁻ form SBAER:

• R-N·Cl + NaOH → R-N·OH + NaCl

Weakly basic NH₄OH is generally insufficient for regenerating SBAERs. SBAERs, due to their strong basicity, require more regenerant than the theoretical amount.

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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)

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