Analyte: Weak Anion, pKa 5.0
R-COOH R-COO- R-COO-
R-COOH R-COO- R-COO- Sorbent: NH2, pKa 9.8 R-NH3+ R-NH3+ R-NH2
R-NH3+ R-NH3+ R-NH2Analyte: Strong Anion
R-SO3- R-SO3- R-SO3-
R-SO3- R-SO3- R-SO3-
Sorbent: NH2, pKa 9.8 R-NH3+ R-NH3+ R-NH2
R-NH3+ R-NH3+ R-NH2pH 3
pH 7
pH 11
Weak
Anion Exchange (NH2)