Chelating Resins

Chelating resins are sub-group of ion exchange resins with polymer matrix and chelating function groups. They are designed to selectively bind and remove metal ions from aqueous solutions through chelation. These resins have functional groups that can form multiple bonds with a single metal ion, creating a stable chelate complex. They are highlighted from other typical resins due to their unique selectivity of targeted ions in an environment of a high concentration of competitive ions. Chelating resins are widely used in various applications, including water treatment, metal recovery, and chemical analysis.

Chelating resins typically have the following structural components:

• Matrix: The polymer matrix includes synthetic organic polymers and natural organic polymers, which are insoluble but swollen in water and a variety of organic solvents.
• Chelating functional groups. Chelating resins works by the formation of strong complexes with the selected ions through the chelating functional groups. Different function groups have specific metal selectivity.
  • Iminodiacetic acid (IDA) is the most popular chelating groups which can form complexes with various elements.
  • Aminomethyl Phosphonic acid (AMPA) is effective for extraction of Indium (In), rare earth elements (REEs), uranium (U), and thorium (Th)
  • Chelating groups containing S donor atom, such as Thiol, Thiourea, and Thiouronium, are widely used for chelating resins and have high affinity for elemental silver (Ag), mercury (Hg), copper (Cu), and plumbum (Pb).

• LSC710, Iminodiacetic type, used for heavy metal removal from solutions
• LSC7105, Iminodiacetic type, macroporous, weak acid
• LSC750, Amino phosphonic type, used for Purification of secondary brine
• LSC7500, Amino phosphonic acid type, weak acid, macroporous
• LSC7100, Amino phosphonic acid type, macroporous, weak acid
• LSC760, Amino phosphonic acid type, used for Fluorine removal from solutions
• LSC743, Thiol type, used for Mercury removal
• LSC740, Thiol type, used for Mercury removal
• LSC724, Thiourea type, high precision mercury recovery
• LSC720, Thiouronium type, used for heavy metal removal, Au, Pt, Pd, Hg, etc.
• LSC790, D2EHPA Impremented type, used for Scandium&Zinc recovery
• LSC772, Cyanex 272 impremented type, used for Cobalt removal from nickel sulfate solutions
• LSC718, Barium Salt Impregnated type, used for selective removal of Radium
• LSC495, Bispicolylamine type, used for separation of copper, nickel and cobalt, etc.
• LSC660, Guanidine type, used for gold recovery from Alkaline Cyanide Leach
• LSC730, Phosphonic and Sulfonic Acid type, used for Iron removal in acidic solution
• LSC485, Hydroxypropyl-picolylamine type, used for Nickel recovery
• LSC770, Polystrene type, weak base anion resin, with macroporous Matrix
• LSC788, Quaternary Ammonium type, strong base, used for selective removal of Uranium
• LAR714, Iron loaded type, used for highly arsenic removal
• LSC780, N-Methylglucamine, used for Boron removal

• High Selectivity: Chelating resins are highly selective for certain metal ions, allowing for the effective separation and removal of specific metals.
• Strong Metal Binding: The chelating groups form strong complexes with metal ions, making the resins highly effective in metal recovery and purification.
• Versatility: Chelating resins can be designed for different applications by modifying the chelating groups to target specific metals.
• Regenerability: These resins can be regenerated by washing with appropriate reagents, allowing for repeated use.

Chelating resins are widely used for metals removal, recovery, and enrichment applications. Chelating resins with various functional groups provide highly metal selectivity, including decalcification of brine, removal of boron (B) from potable water, recovery of precious metals such as gold (Au), platinum (Pt), palladium (Pd), and removal of heavy metal such as copper (Cu), nickel (Ni), zinc (Zn), manganese (Mn), and mercury (Hg).:

• Water Treatment: Removal of heavy metals and toxic ions from industrial wastewater and drinking water. They are effective in treating water contaminated with boron, lead, cadmium, and other hazardous metals.
• Metal Recovery: Extraction of valuable metals from ores or scrap materials. For example, they are used in the recovery of precious metals like gold (Au), Platinum (Pt), Palladium (Pd) and silver from mining operations.
• Chemical Analysis: Separation and purification of metal ions in analytical chemistry. Chelating resins are used in the preparation of samples and in chromatography techniques.
• Pharmaceuticals: Removal of metal contaminants from pharmaceutical products and raw materials.
• Environment: Remediation of contaminated soils and sediments, particularly in areas affected by industrial pollution.