Custom Mixed Bed Resins

INQUIRY

Mixed bed resin refers to a bed in which two resins are charged into the same exchanger in a certain proportion and are exchanged in operation at the same time in a mixed state. The custom mixed bed resins provided by Alfa Chemistry include the following types:

EDM treatment
Condensate polishing
Nuclear deionization
Aquarium water treatment
Mixed bed resins with indicator
Other mixed bed resins

About mixed bed resins

The ion exchange resin mixed bed is usually used as a deep desalination equipment for reverse osmosis or electrodialysis desalination and ion exchange desalination processes. The cation exchange resin exchanges with the cations of the incoming water to release H⁺, and the anion exchange resin exchanges with anions to release OH^-. Because the anion and cation resins are mixed together, H⁺ and OH^- can be combined into H₂O immediately, and the exchange reaction has been going positive. Therefore, the exchange is complete, and high-purity product water can be obtained. In the positive or negative bed, the exchanged H⁺ or OH^- ion concentration continues to accumulate, and the reverse reaction is enhanced, resulting in incomplete exchange. After the mixed bed fails, the resin needs to be layered, regenerated with acid and alkali to restore its exchange capacity, and then mixed and put into use.

A new way of performing pH gradient-based protein separations using a mixed-bed column comprising a small-pore weak base resin and a large-pore strong base resin and a step change in pH at the column entrance is introduced. (Vetter T A, et al. 2014) The approach effectively decouples intracolumn generation of pH gradients, which ensues from ionic interactions with the weak base resin, from protein separation, which ensues from interactions with the strong base resin ligands, resulting in a process that is more easily predictable, less prone to the effects of protein loading on the pH gradient, less susceptible to hydrophobic interactions between protein and resin surface, and more flexible. The approach is demonstrated successfully using a tertiary amine resin as the weak base component together with a range of commercial strong anion exchangers with quaternary amine functionality. The principle is shown in Fig. 1.

Fig.1 Schematic of mixed-bed approach for protein separations by anion exchange

Alfa Chemistry has a strong resource library and expert team. We will do our best to provide you with the best quality customized service. Our customers can directly contact our experts and provide timely feedback on any online inquiries. If you are interested in our services, please contact us.

Reference

Vetter T A, et al. Mixed-Beds of Strong and Weak Anion Exchange Resins for Protein Separations with Step-Induced pH Gradients. Separation Science & Technology, 2014, 49(4):477-489.