Municipal Water Applications

Arsenic is a chemical element with symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but only the gray form is important to industry.
The primary use of metallic arsenic is in alloys of lead (for example, in car batteries and ammunition). Arsenic is a common n-type dopant in semiconductor electronic devices, and the optoelectronic compound gallium arsenide is the second most commonly used semiconductor after doped silicon. Arsenic and its compounds, especially the trioxide, are used in the production of pesticides, treated wood products, herbicides, and insecticides. These applications are declining, however A few species of bacteria are able to use arsenic compounds as respiratory metabolites. Trace quantities of arsenic are an essential dietary element in rats, hamsters, goats, chickens, and presumably many other species, including humans.Arsenic is notoriously poisonous to multicellular life. Arsenic trioxide compounds are widely used as pesticides, herbicides and insecticides. As a result, arsenic contamination of groundwater supplies is a problem that affects millions of people around the world.

Arsenate is a divalent anion with affinity for anion resins similar to but slightly lower than that of sulfate Arsenate can be exchanged by strong base anion exchange resins and then adsorbed into the iron hybrid adsorbent of ASM-10-HP.

Except for Gallium arsenide (used a semiconductor), other arsenide compounds are generally only of academic interest. Gallium arsenide is an important semiconductor because it has much lower electrical resistance than silicon and therefore lower power use and less heat generation.

In most cases arsenite should be oxidized to arsenate so that it is converted to a form more easily removed. Oxidation can be accomplished with chlorine or with oxygen catalyzed by various redox medias.

Disinfection By-Product (DBP) are formed when chlorine reacts with organic compounds in water supplies. The removal of organic prior to chlorination can eliminate the DBP potential, otherwise the DBPs need to be removed by activated carbon.

Strong base anion resin have good affinity for nitrate. The higher amines (triethylamine, tributylamine, etc.) have increased affinity for nitrate and decreased affinity for divalent ions such as sulfate, making them preferred for many applications.

Naturally occurring organic matter (NOM) is readily removed by strong base anion resins. Acrylic strong base resins and styrenic resins with high porosity work better because they are easier to regenerate.

Perchlorate is a relatively weak oxidant, used as an oxygen source in rocket fuel. Perchlorate is also a contaminant in ammonium nitrate fertilizer.
Although all strong base anion resin have high affinity for perchlorate, the higher amines (such as tributylamine) have exceptional affinity for perchlorate.

PFAS compounds have been used in industry and consumer products worldwide since the 1940s. Their remarkable hydro- and oleophobic characteristics (ability to repel both oil and water) give them utility in a seemingly endless array of applications including nonstick cookware, water repellent clothing, stain resistant fabrics and carpets, product packaging, some cosmetics, some firefighting foams, and literally tens of thousands of other products that resist grease, water, and oil.

More than 500 forever chemicals are being actively used in products and industries around the world. A United States Environmental Protection Agency (EPA) toxicity database, DSSTox, lists over 14,700 PFAS compounds in existence, while other toxicity databases lists many multiples more.

ResinTech offers a variety of PFOS & PFAS remediation options, including PFOS filtration and PFOS testing kits to help you identify and remove these chemicals from your needed water.

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Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily combines with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2). All isotopes of radium are highly radioactive, with the most stable isotope being radium-226, which has a half-life of 1600 years and decays into radon gas (specifically the isotope radon-222). When radium decays, ionizing radiation is a product, which can excite fluorescent chemicals and cause radioluminescence.

Radium is the daughter product of uranium decay and is heaviest alkaline earth metal. It was discovered in the form of radium chloride by Marie and Pierre Curie in 1898. They extracted the radium compound from uraninite and published the discovery at the French Academy of Sciences five days later. Radium was isolated in its metallic state by Marie Curie and André-Louis Debierne through the electrolysis of radium chloride in 1911.It has the property of luminescence and was once used to make watch dials glow in the dark as well as for various quack products

Radium forms a divalent cation in water and can be removed by water softening resins, along with other hardness ions. Except for the first exhaustion cycle, radium leakage occurs shortly after hardness leakage occurs, therefore the resin is used as an ordinary softener with brine regeneration at regular intervals.

The highly crosslinked macroporous cation resin have extended first cycle operation past hardness break and can be used in single use applications when hardness and TDS are not too high. RSM-50 has barium sulfate deposited in the pores of the resin. Radium is first exchanged and then transfer to the precipitant, allowing much higher loading and longer throughput.