HETEROGENOUS ION-EXCHANGE MEMBRANES RALEX

The RALEX membranes are heterogeneous ion-exchange membranes produced in MEGA a.s. Stráž pod Ralskem, Czech Republic, since 1985.

The membranes are produced in the form of foils composed of fine polymer particles with ion exchange groups anchored by polymer matrix and reinforced by fitted fabrics which improves the mechanical properties of the membrane.

Membranes are divided by the type of ions they let out into cation-exchange membranes (let out cations) and anion-exchange membranes (let out anions).

A characteristic feature of ion exchange membranes consists in the fact that they contain functional ion exchange groups which are covalently bound to polymer skeleton. The charge of bounded ions in the membranes is balanced by quivalent charge of so called counter ions. If polymer is placed in water solution, it swells and becomes pliable. In the swelled polymer, ions may move in a free way by a diffusive mechanism or by action of the electric field. The membrane behaves like ion conductor in the electric field and transmit ions of the charge with high selectivy. Cation-exchange membrane RALEX CMH transmits cations, and anion-exchange membrane RALEX AMH transmits anions while both types of membranes prevent to hydrodynamic flow of solvent.

Selectivity and flow blockage of solvent are then used in particular separation processes, e.g. elektrodialysis (ED), electrophoresis (EF), electrodeionization (EDI) etc.

The membranes are prominent for their excellent mechanical and electrochemical properties, an especially low electric resistance, high permselectivity, high resistance to industrial membrane poisons and aggressive chemicals, good thermal resistance, they can normally work in the wide pH range etc. The RALEX membranes are brought into working state by swelling in water, conditioning and adapted accordingly to the used systems. The membranes can be redesiccated and reswelled and in the swelled state are flexible very good. They cannot be deformed in dry state too much.

The membranes RALEX are mainly suitable for application in electromembrane processes like electrodialysis (ED), electrophoresis (EF), electrodeionization (EDI) or membrane electrolysis (ME) which are used for water treatment, separation of nonelectrolyte-electrolyte in organic and pharmaceutical industries, concentration of dissolved substances, utilization of whey, etc.

These membranes have a wide range of utilization in the series of separation methods provided in both laboratory and industrial scales. Processing of industrial solutions enables to use these membranes for continual, waste free, ecologically and economically advantageous technologies.

Advantages of Using Membranes RALEX

• individual types of membranes are modified and optimised in production with respect to their use
• they show ion-exchange and separation characteristics only in so-called swelled condition
• they have a wide range of utilisation in separation, demineralisation and concentration processes in which the gradient  of electric potential is used as the driving force
• they have excellent characteristic properties, namely good dimension stability, easy handling especially in swelled condition, low electric resistance, high permselectivity, chemical stability in wide range of pH with resistance against many aggressive chemicals and membrane poisons, good thermal stability and long life cycle (up to 10 years, based on the environment)
• they are less prone to repeated dehumidification and swelling
• they can be regenerated using suitable chemical and mechanical procedures

In the Area of Membrane RALEX MEGA a.s. Offers 

• cation-exchange membrane RALEX CM or CMH
• anion-exchange membrane RALEX AM or AMH

Production of membrane RALEX is certified according to standards CSN EN ISO 9001:2001 and 14001:2005. Some types of membranes RALEX are certified for use in food-processing and pharmaceutical industries.

Examples of Membrane RALEX Application

• especially for application in electromembrane processes:
  • electrodialysis (ED)
  • electrophoresis (EF)
  • electrodeionization (EDI)
  • membrane electrolysis (ME)
• for desalination and concentration of sea and brackish or industrial water
• for separation of systems electrolyte/non-electrolyte
• for demineralisation and concentration of ions in chemical, pharmaceutical and food industries
• to keep chemical balance of ions in electrophoresis

Technical Data of Membranes RALEX

* Type of the textile fibers (PES, PAD) is recommended to be consult with us according to the application.

Standard Formate of Membrane RALEX

Membranes RALEX AM(H), CM(H) (PES, PAD) for electrodialysis, electrodeionization and membrane electrolysis.

Membranes RALEX^® AMH5E HD, CMH 5E for electrophoresis.

In case of any requirements for nonstandard formats, please don’t hesitate to contact us. We are willing to discuss it and to prepare the quotation.