Selective Electrodialysis Technology

What Is Selective Electrodialysis Technology?

Selective electrodialysis (SED) technology is an electrochemical membrane process used for the selective separation and purification of ions from solution streams. Unlike conventional electrodialysis, which separates all ions indiscriminately, SED enables the selective transport of specific ions through ion-selective membranes under the influence of an electric field. This selective transport leads to the purification of targeted ions, making it an attractive solution for various industries requiring precise ion separation.

How Selective Electrodialysis Works

SED operates based on the principle of ion-selective membrane permeability and the application of an external electric field. In the SED process, a feed solution containing mixed ions is passed through a series of alternating ion-exchange membranes and selective ion-selective membranes. When an electric potential is applied across the membranes, the ion-selective membranes allow only specific ions to transport through, while blocking others. This selective transport results in the targeted ion's concentration to increase in one stream and decrease in the other, achieving high-purity separation.

Work principle of SED. [1]

Membrane Materials for Selective Electrodialysis

The membrane materials used for selective electrodialysis (SED) play a crucial role in determining the technology's selectivity and performance. Below is a quick selection guide for high quality ion exchange membranes/selective perms membranes from Alfa Chemistry.

Catalog	Type	Exchange Capacity	Selectivity	Feature	Application	Price
ACMA00033501	Anion		90%	Single ion selective permeability		INQUIRY
ACMA00033509	Anion		90%-95%	Single ion selective transmission	Food desalination Inorganic salt desalination and concentration Groundwater nitrogen removal	INQUIRY
ACMA00033511	Anion	0.5meq/g-0.6meq/g	90%-95%	High ion selective permeability, low electrical resistance, high mechanical strength, chemical resistance	Desalination of pharmaceutical and chemical intermediates Amino acid desalting Sugar desalination Desalination of sweeteners Desalination of animal and plant extracts	INQUIRY
ACMA00033513	Anion	1.31meq/g	90%-95%	High ion selective permeability, low electrical resistance, high mechanical strength, chemical resistance	Separation and purification of acid and metal salt mixture Waste acid recycling	INQUIRY
ACMA00033514	Anion	0.9meq/g-1.0meq/g	90%-95%	High ion selective permeability, low electrical resistance, high mechanical strength, chemical resistance	Desalination of pharmaceutical and chemical intermediates Amino acid desalting Sugar desalination Desalination of sweeteners Desalination of animal and plant extracts	INQUIRY
ACMA00033520	Anion	2.1meq/g	90%	Excellent selective permeability, low resistance, high mechanical strength	Dedicated to gold salt production	INQUIRY
ACMA00033521	Anion	≥2.0meq/g	≥92%	High density, high selective permeability, resistance to organic pollution	Betaine special film Sugar separation membrane Special membrane for ammonium nitrate	INQUIRY
ACMA00033556	Cation		90%	Hydrogen ion selective permeation		INQUIRY
ACMA00033557	Cation		90%	Single ion selective transmission	Acid recovery Metal separation Salt manufacturing	INQUIRY
ACMA00033561	Cation	0.8meq/g-1.0meq/g	90%-95%	High ion selective permeability, low electrical resistance, high mechanical strength, chemical resistance	Desalination of pharmaceutical and chemical intermediates Amino acid desalting Sugar desalination Desalination of sweeteners Desalination of animal and plant extracts	INQUIRY
ACMA00033565	Cation	≥2.2meq/g	≥92%	High density, high selective permeability, resistance to organic pollution	Betaine special film Sugar separation membrane Special membrane for ammonium nitrate	INQUIRY

Applications of Selective Electrodialysis

SED technology finds diverse applications across various industrial domains, such as acid recovery, desalination, and resource regeneration from complex solutions.

Water Desalination

SED can be utilized for selective removal of monovalent or divalent ions, contributing to the cost-effective desalination of brackish water and seawater. For example, Zi Hao Foo et al. achieved sustainable recovery of lithium from a hypersaline lake through selective electrodialysis.

SED for Lithium Recovery. [2]

Acid Recovery

In the context of acid recovery, SED offers an efficient and environmentally sustainable solution for the selective separation of inorganic acids from metal ions, contributing to the circular economy by enabling the reclamation of valuable acids from waste acid streams. Haiyang Yan et al. developed a novel electrodialysis (SBMED) method for the conversion of high-purity monobasic and dibasic acids.

SBMED for Acid Recovery. [3]

Food and Beverage Industry

SED technology can assist in the purification of fruit juices, wine, and dairy products by selectively removing unwanted ions and impurities, enhancing product quality and shelf-life.

Pharmaceutical and Biotechnology

SED can be employed for the selective purification of pharmaceutical compounds, separation of amino acids, and isolation of specific ions in biotechnology processes.

Environmental Remediation

SED holds potential for treating industrial effluents, wastewater, and contaminated groundwater by selectively removing pollutant ions, contributing to environmental sustainability.

References