NEWater Anion Exchange Resin

NEWater offers a wide variety of ion exchange resins packed securely before shipment. Our anion exchange resins are an essential part of the ion exchange process to remove unnecessary water impurities. In this process, the ionized water is pumped into a pressure tank containing anion exchange resin. To draw out the anionic impurities, the positively charged (+) anion resin beads attract them. Afterward, when the resin beads release the non-pollutant ions (OH-) they’ve been holding onto to take their position in the pollutant anions. After passing through the pressure tank, the water is nearly pollutant anions-free and ready to be utilized or reused.

NEWater’s ion exchange resins are widely utilized in water treatment systems across a wide range of industries, including pharmaceuticals/laboratories, industrial water treatment, sugar decolorization, water refilling, and many others. We promise that our products and services are of the highest possible quality, efficient, economical, and ecologically sustainable, and provide a 1-year warranty. Ensure speedy transportation and secured packaging by trusting our helpful personnel to assist you with a 24-hour response and quick response.

For your ion exchange resins queries, please email us at info.@newater.com.

The Ultimate FAQ Guide for Anion Exchange Resins

Nearly all domestic, commercial, and industrial applications are dependent on water. Some of these applications demand a unique quality of water, which can only be generated with the aid of customized water treatment systems. Anybody can presently purchase a water treatment system tailor-made to solve a specific water problem. Ion exchange systems are great examples of water treatment systems specifically designed to solve a particular water problem. Underneath, we will be narrowing our today’s discussion to anion exchange resins and their specific roles in water treatment.

➣What is an Anion Exchange Resin?

An anion exchange resin is a polymer that provides a medium for the exchange of ions, particularly negatively charged ions. These resins are mostly employed together with cation exchange resins to facilitate optimal deionization. They are however also functional when deployed as standalone resin filters. In this capacity, their applications range from denitrification to partial demineralization.

Typical anion exchange resins consist of polystyrene polymers even though the composition of their functional groups may be dissimilar.  The functional groups in anion exchange resins are essentially positively charged. This means that they have a high affinity for negatively charged ions in the water. The pollutant anions attracted to the cationic functional groups are subsequently substituted by the hydroxide (OH-) ions held by the resin beads.

A comprehensive ion exchange system or water deionizer unit contains both the anion and cation exchange resins. However, the two resins can be alienated and deployed in distinct water filtration exercises to accomplish distinct goals. We are seasoned manufacturers of both anion and cation exchange resin filters. Our equipment is uniquely and intelligently designed to facilitate cost-efficiency, longevity, and user convenience.

➣What is the Role of Anion Exchange Resins?

They are in essence ion exchangers designed to eradicate a specific kind of ionic impurities. They are configured to include a cationic functional group and negatively charged resin beads (OH-). As such, anion exchangers only eliminate negatively charged ions. Beneath, we will briefly discuss the essential role carried out by anion exchange resins.

●      Nitrate removal.

High nitrate levels in drinking water are likely to cause dizziness, bluish or gray skin, fatigue, or even a fast heart rate. Therein, it is essential to monitor and control the level of nitrate in water. This can be achieved by filtering the water using an anion exchange resin filter. The effective elimination of nitrate is ordinarily accomplished using strong base anion (SBA) resins in the chloride form.

●      Partial demineralization.

Demineralization is the process of flushing out virtually all ionic components from water. To completely deionize or demineralize water, you need a water deionizer system fitted with both the anion and cation exchange resins. Standalone anion resins can only deionize the water partially. They only remove anionic contaminants such as chloride (Cl-), carbonate (CO3-), and nitrate (NO3-).

●      Dealkalization.

Dealkalization of water is primarily accomplished using Type II anion exchange resins. This particular type of resin is regenerated using sodium chloride (NaCl). Typical alkalinity ions eradicated by the anion exchange resin include carbonate, hydroxyl, and bicarbonate ions.

●      Desilication.

Silicon is an aggressive pollutant found in most water streams. Certain compounds of silicon e.g. silicon tetrachloride can have devastating effects on human beings. For instance, difficulties in breathing and eye irritation. Desilication is the process of removing these silica compounds from water. The resins replenished using caustic soda (NaOH) are ideal for silica removal alongside lime softening, reverse osmosis, and ultrafiltration.

➣How do Anion Exchange Resins Function?

Anion exchange resins get rid of anionic contaminants through a process referred to as ion exchange. This is a reversible process that replaces objectionable ions with non-pollutant ions like hydroxide (OH-) and hydrogen (H+). However, prior to passing the feed water through the anion exchange resins, it is advisable to pretreat it. Preliminary treatment is usually undertaken using sediment filters, which filter out debris, colloids, and suspended solids with the potential of blocking the resin bed.

The ionized water is then fed into a pressure vessel housing the anion exchange resin. As it penetrates through the anion resin beads, the anionic impurities in the water are drawn by the positively charged functional groups. Subsequently, the resin beads discharge the held non-pollutant ions (OH-) to replace the pollutant anions. Water deprived of virtually all anions exits the pressure tank ready for use or further treatment.

In comprehensive ion exchange systems, the feed water is initially filtered using a cation exchange resin. This strips off all pollutant cations consequently replacing them with non-pollutant (H+ or Na+ ions). It is worth noting that the process of ion exchange depends on the configuration of the exchange resins. For instance, the ion exchange process in mixed-bed deionizers occurs in a single vessel while in two-bed exchangers, cation removal and anion removal are undertaken in separate vessels. Here is a video elaborating on how ion exchange resins work.

➣What Are the Different Types of Anion Exchange Resins?

Anion exchange resins are characteristically ion exchange resins that interchange negatively charged pollutants with less objectionable ions like hydrogen (H+). These exchange resins are typically regenerated using basic solutions like caustic soda. Underneath, we will be walking through the two main types of anion exchange resins， strong base anion (SBA) resins and weak base anion (WBA) resins.

●      Strong base anion (SBA) resins.

The naming of strong base anion resins is primarily informed by the strength of their amino functional groups. SBA resins consist of a quaternary ammonium group and are quite alkaline. They mostly recharged or regenerated using caustic soda. Strong base anion resins are divided into;

• Type 1 resins.
• Type 2 resins.
• Acrylic resins and
• Macro-porous resins.

Type 1 SBA resins are mainly utilized to eradicate silica, nitrates, perchlorate, and sulfates. They are also ideal for partial demineralization. Type 2 SBA resins on the other hand are utilized in applications that are not necessarily sensitive to silica, and applications that necessitate low caustic levels.

●      Weak base anion (WBA) resins.

Weak base anion resins are distinguished by their non-reliance on exchangeable ions. Unlike other ion exchange resins, they lack exchangeable ions and instead rely on the adsorption of SO4- and Cl-. The functional groups of WBA resins are amine and regeneration is usually undertaken using ammonia, sodium hydroxide, or sodium carbonate. They are primarily used in acid adsorption, partial deionization, and TOC removal. WBA resins are however limited when it comes to the elimination of weak acids.

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➣What Do You Use to Regenerate Anion Exchange Resins?

During an in-service cycle, an anion exchange resin picks up suspended solids and may ultimately lose its exchange capacity. This is primarily caused by the accumulation of pollutant ions in the resin beads. The anion exchange resin consequently loses its effectiveness and the quality of water generated depreciates. This is often remedied by initiating the resin regeneration process.

Regenerating anion exchange resins requires one to flush through the resins, a base solution. Strong base anion resins for instance are typically recharged using a solution of sodium hydroxide (NaOH) while weak base anion resins are often replenished using ammonia (NH3), sodium carbonate (Na2CO3), and sodium hydroxide (NaOH).

The anion exchange resin regeneration process commences with backwashing. This process flushes out impurities trapped by the resin beads. After, the regeneration solution is administered into the resin bed at a slow flow rate. Subsequently, the clean water is flushed through the resin bed at a low flow rate in a process known as the slow rinse. This dislodges the remaining regenerate before the fast rinse process is initiated. This is how resin regeneration is undertaken.

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➣How Are Anion Exchange Resins Different from Cation Exchange Resins?

Anion and cation exchange resins are both essential components of ion exchange water systems.  They are the mediums used to exchange undesirable ionic impurities for less objectionable ions. Cation IX resins are primarily tasked with interchanging pollutant cations with non-pollutant ions. They are made of anionic functional groups with high affinities for positively charged ions. Therein, they extract positively charged ions like Ca2+, Fe2+, and Mg2+.

Anion exchange resins on the other hand are endowed with cationic functional groups and their resin beads are often charged with hydroxide (OH-) ions. They are mainly used to extract negatively charged ions like Cl-, NO3- and CO3-. However, both anion and cation exchange resins are often used in tandem to completely deionize water.

They can be housed in separate pressure vessels as in dual-bed ion exchangers or intimately blended and housed in one pressure (mixed-bed ion exchangers). We manufacture anion exchange filter resins as well as cation exchange filter resins. To learn more about these distinct filters or to place an order, kindly visit our website.

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➣What are The Distinct Processes Used to Regenerate Anion Exchange Resins?

Resin regeneration can be accomplished in either of two methods; reverse flow or co-flow regeneration. The regeneration methods are essentially named after the distribution route the regeneration chemical takes.

●      Reverse flow regeneration.

Reverse flow regeneration is alternatively referred to as counter-flow regeneration. This methodology flushes the regeneration solution in a direction contrary to the normal service flow. If the regular flow is from top to bottom, the regenerant is fed from bottom to top and vice versa. This ensures that resin beads that are less exhausted are regenerated first thereby facilitating the efficient use of the regenerate. Counterflow regeneration is mainly used in regenerating packed bed ion exchange columns. It mitigates the leakage of impurities and consumes relatively smaller regenerants.

●      Co-flow regeneration

Unlike reverse flow regeneration, co-flow regeneration runs the regeneration solution in a route similar to the conventional service flow. Ordinarily, this is from top to bottom. This method is not ideal for applications that demand high quality or applications operating at a large scale. This is because extravagant volumes of regeneration solution would be necessitated to regenerate the exhausted resins.

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➣Can Anion Exchange Resins Soften Hard Water?

No. Water hardness is essentially caused by calcium (Ca2+) and magnesium (Mg2+) ions. These ions are divalent and positively charged. Anion exchange resins are specifically designed to seize negatively charged pollutant ions and subsequently replace them with hydroxide (OH-) ions. This is because they have cationic active sites, which attract negatively charged ions. For this reason, anion exchange resins are chiefly used in de-alkalization, partial demineralization, denitrification, and desilication applications.

Hardness ions are positively charged (Mg2+ and Ca2+). Therein, they are attracted by the anionic functional groups found in cation exchange resins. The Na+ or K+ ions held by the cation exchange resins are consequently discharged and they replace the hardness ions to generate soft water. Ion exchange resins specialized for water softening are regenerated using sodium or potassium salts.

In addition, there are other water softener systems that you can exploit. For instance, a nanofiltration filter system. This is a membrane filtration system that traps divalent and trivalent ions. Hardness-causing ions are classified under divalent ions and are technically extracted by the NF membrane. For the best water softener units, get in touch with NEWater. Our prices are hugely discounted and we offer door-to-door delivery services.

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