Chelating resins are a subgroup of ion exchange resins that have a high selectivity of at least one particular counter-ion species. The interaction of a functional group (ligand) of chelating resin and metal (in form of cation or oxoanion) is selective with respect to the nature of the metal. In the case of chelating resins counter ions are bound to resin by coordinate covalent bond or by its combination with electrostatic interactions. In the case of ion exchange, electrostatic force between oppositely charged functional group and ion in solution plays the main role. SLC 714 is an iron loaded (III) chelating resin used as an adsorbent for removing Arsenic from potable water and waste water.
About Heavy Metals
The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. These metals have been extensively studied and their effects on human health regularly reviewed by international bodies such as the WHO. Heavy metals have been used by humans for thousands of years. Activities such as mining and construction can release large amounts of heavy metals into nearby ground water sources. Some older fruit orchards may contain high levels of arsenic, once used as a pesticide. At high levels, these metals pose a health risk. Underground rocks and soils may contain arsenic, cadmium, chromium, lead, and selenium. However, these contaminants are not often found in household wells at dangerous levels from natural sources. Household plumbing materials are the most common source of lead and copper in home drinking water. Corrosive water may cause metals in pipes or soldered joints to leach into your tap water. Your water’s acidity or alkalinity (often measured as pH) greatly affects corrosion. Temperature and mineral content also affect how corrosive it is. They are often used in pipes, solder, or plumbing fixtures. Lead can cause serious damage to the brain, kidneys, nervous system, and red blood cells. The age of plumbing materials — in particular, copper pipes soldered with lead — is also important. Even in relatively low amounts these metals can be harmful. EPA rules under the Safe Drinking Water Act limit lead in drinking water to 15 parts per billion. Since 1988 the Act only allows “lead free” pipe, solder, and flux in drinking water systems.
About LSC 710
LSC 710 is an iminodiacetate chelating resins of weak acidic, macroporous cation type. It was specifically developed for selective extraction of heavy metals, in particular copper. Due to its high bead integrity, excellent chemical and physical stability ensures high performance in conventional resin columns, as well as filter cartridges.
The selectivity depends on pH and is as listed below:
Under Acidic condition:
Copper > Vanadium >(VO) > UO2> Lead > Nickel > Zinc > Cadmium > Iron(II) > Beryllium >
Manganese > Calcium > Magnesium > Strontium > Barium > Sodium.
Under Alkaline condition:
Calcium> Magnesium >Strontium> Nickel> Barium > aluminum >Iron(II) > Copper > Iron(II) >
Copper>Cadmium> Vanadium > tungsten > Sodium
Apart from Potable applications, LSC 710 is also used in waste water treatment applications. Wastewater treatment systems face increasingly stringent discharge limitations, in many cases lower than the limits for the supplies used as feed water. Ion exchange resins and adsorbent medias are often ideally suited for removal of specific contaminants and/or for polishing the effluent from other wastewater treatment processes.