Strong acid cation exchange resin
Generally, the sulfonic acid group -SO3H is used as the active group. The ionization degree of the active group of the strong acid resin is large, and it is not affected by the pH of the solution, and the ion exchange reaction can be carried out in the range of pH 1-14. The strong acid resin has weak binding force with H+, it is difficult to regenerate the hydrogen form, and the acid consumption is large, which is generally 3-5 times the exchange capacity of the resin. It is mainly used for the preparation of soft water and non-salt water, and is also widely used in the extraction and purification of streptomycin, kanamycin, gentamicin, lysine, etc.
Weak acid cation exchange resin
Weak acid cation exchange resin refers to ion exchange resins containing weak acid groups such as carboxyl group (-COOH), phosphoric acid group (-PO3H2), phenol group (-C6H4OH), etc. Among them, the ion exchange resin containing carboxyl group is the most widely used. The degree of ionization of weakly acidic groups is greatly affected by the pH of the solution, and almost no exchange reaction occurs in acidic solutions, and only in solutions with pH ≥ 7 have good exchange capacity. As the pH increases, the exchange capacity increases. Sodium carboxylate resin is not easy to be washed to neutrality. Generally, it can be washed until the pH of the outlet is 9-9.5, and the amount of washing water should not be too much. Weak acid resin has strong binding force with H+, which is easy to regenerate into hydrogen form and consumes less acid.
Strong base anion exchange resin
Strong basic anion exchange resin is an ion exchange resin with a quaternary amino group as the exchange group. The active groups are trimethylamino[-N(CH3)3OH, type I], dimethyl-β-hydroxy-ethylamino[-N (NH3)2(C2H4OH)OH, type II], type I is more basic than type II and has a wider range of uses. The strong basic active group has a large degree of ionization, and it can show ion exchange function in acidic, neutral and even alkaline media. The chlorine type is more stable than the hydroxyl type and has better heat resistance, and most of the commodities are chlorine type. The strong basic resin has a weak binding force with OH-, which is difficult to regenerate and consumes a large amount of alkali. Such resins are often used in the preparation of anhydrous brine and the separation and purification of drugs.
Weakly basic anion exchange resin
Weakly basic anion exchange resins are ion exchange resins with primary amine groups (-NH2), swollen amine groups (-NHR) or tertiary amine groups (-NR2) as exchange groups. The degree of dissociation of weakly basic groups in water is very small, and the ion exchange function is only shown in neutral and acidic media, that is, the exchange capacity is greatly affected by the pH of the solution, and the lower the pH, the greater the exchange capacity. The weak basic group has a strong binding force with OH-, is easy to regenerate into a hydroxyl type, and consumes less alkali.
Welch Materials ion exchange chromatography media✦
➭ Q/SP/DEAE/CM Tanrose FF Fast Flow Agarose Matrix Ion Exchange Media
➭ Q/SP Tanrose HP High Resolution Agarose Matrix Ion Exchange Medium
➭ Q/SP Tanrose XL High Capacity Agarose Matrix Ion Exchange Medium
➭ Q/SP Tanrose BB Large Particle Agarose Matrix Ion Exchange Medium
➭ DEAE/CM Tandex Dextran Matrix Ion Exchange Media