Electro Membrane Processes

Products/Processes that can be offered from the discipline to be marketed

Development of domestic ED unit.

ED UnitAqua desalin ED domestic Unit

The Institute has developed domestic ED unit to desalinate brackish water to obtain potable water required for domestic purpose. This newly developed unit treats about 3,000 ppm or less TDS brackish water and gives potable water of 500 ppm total dissolved solids at an estimated rate of around 10 - 12LPH/50 -60 LPH . The power consumption would be of 2.0 - 2.5 KWH per cubic meter of product water. An inbuilt ozonator is incorporated in this unit to destroy the pathogen to make the product water safe for drinking.

Aqua desalin ED domestic Unit

Development of electro - deionization system

EDThe institute has also developed a continuous electro deionization (CEDI) system for the production of ultra pure water/high purity water.. This unit could produce water having a resistivity up to 18.2 mega Ώ cm  at a capacity of 12 lit/hr. This Product was developed using indigenously developed interpolymer ion exchange membranes.

Designing and development of nano composite membranes

Organic-inorganic nanocomposite (based on PVA-SiO2) membranes were developed by sol-gel process under acidic conditions. The nano-structured organic-inorganic hybrid materials are currently the objects of intensive research, because they combine in a single solid both the attractive properties of a mechanically and thermally stable inorganic backbone and the specific chemical reactivity and flexibility of the organo-functional group. Organic-inorganic hybrid membranes, with acidic (–SO3H, –PO3H2, and –COOH) functional groups and basic (-N+(CH3)3Cl)  functionality, were prepared as cation- and anion-exchange membrane.  Properties of the developed membranes were largely dependent on the way of preparation (catalyst, temperature, and crosslinking) and the functional groups attached with inorganic as well organic moieties. It was found that phosphonic acid functionalized membranes showed long range of conductivity over a wide temperature while sulphonic acid functionalized membranes showed deterioration in conductivity at higher temperature. This was concluded on the basis of degradation of the functionality at higher temperature.  The physicochemical and electrochemical properties of the developed membranes were found to be comparable with best commercially available membrane (viz. Nafion and Neosepta etc) for energy and electro-membrane devices. 

Heterogeneous–homogeneous composite bipolar membrane

EMP division has developed easy method for the preparation of heterogeneous–homogeneous composite BPM. Single cationic layer of sulphonated poly(ether ether ketone)was prepared by casting and evaporation. After the solidification of first layer, the next layer was casted onto the surface of the former, which then was allowed to dry. This procedure was repeated for cationic, interfacial and anionic layers. Because all polymer solutions were prepared in the same solvent and the contact at the interface layers was firm. These membranes exhibited low water content and resistivity, while high ion-exchange capacity. The efficiency of the developed membrane was assessed for water and salt splitting.

Electrochemical/chemical value addition processes
  • A. Eco-friendly solid brominating reagents (Green bromine). Chemical and Electrochemical methods for the preparation of 2:1 bromide:bromate based solid brominating reagent were developed for bromination of a wide range of organic substrates through substitution mechanism. They are stable, easy to transport, non-hazardous and convenient to use in the bromine reactions in normal experimental conditions. The end liquor contains simple inorganic salts and hence are safe to discharge with nominal treatment.
  • B. Eco-friendly procedures for the preparation of Tetrabromobisphenol-A (TBBPA-largely used flame retardant) has been established with the 2:1 bromide:bromate based solid brominating reagent.

Capabilities & Strength of the Discipline


Industrial/Academic linkages of the discipline

Interaction with industries for effluent treatment & for separation, purification & concentration of chemicals

Recent innovations emerged

Hybrid ED-RO technology for the desalination of sea water desalination for the production of drinking water • CEDI system for the production of ultra pure water/high purity water.

Expertise availability in membrane designing and desalination applications

  • Designing of membranes with desired charge density and porosity for different electro-membrane processes
  • Separation/purification of bioactive molecules by electro-driven membrane separation techniques
  • Consultancy work related to the electro-driven membrane separation technologies

  • Saline water desalination
  • Desalting of industrial mixtures or effluents
  • Technology transfer
  • Domestic ED unit for the treatment of brackish water.
  • Electro deionization technology for the production of ultra pure water
  • ED Package for the desalination of brackish water of various capacities.
  • ED technology package for the desalination of sea water to potable water.
  • ED technology using non conventional energy for desalination of brackish water
  • Production of renewable energy  by reverse elecrodialysis (RED)
  • Hybrid membrane technology(ED-RO) for the desalination of high saline sea water for the production of potable water.
  • Technology package for treating industrial effluents to recover high value chemicals for the pollution reduction.
  • Separation of inorganics and organics or bioactive molecules with very high purity by electrodialysis with conducting spacers.
  • Ion-exchange  membranes  based on  poly ethylene cross linked  styrene-divinyl benzene copolymer.
  • Design of various capacity ED plants for various applications.
  • Electrodialysis  technology for saline water desalination.
  • Electrodialysis technology for the treatment of industrial effluent.
  • Electrodialysis technology for the separation, purification & concentration of inorganics and organics from its mixtures.
  • CEDI technology for the production of ultra pure/ high purity water.