Lithium Hypochlorite in Pools: All You Need to Know

Lithium hypochlorite is an unstabilized, inorganic compound that appears in granular form. Lithium hypochlorite provides 35% available chlorine and 29% active strength. In a 1% solution, it raises the pH to 10.8. Lithium hypochlorite, also known as Lithium Hypo, is a white powder or granule with a high pH (10.8). It provides 35% available chlorine and does not contain stabilizer (cyanuric acid or conditioner). Lithium hypochlorite is manufactured by mixing chlorine gas with caustic soda and then with lithium hydroxide. Lithium hypo is a type of chlorine used for disinfecting swimming pools and is known for its high available chlorine content. Its high solubility and rapid dissolution when dispersed across the pool’s surface make it an appropriate choice for vinyl-lined or dark plaster pools.

What are the Chemical Properties of Lithium Hypochlorite?

Lithium hypochlorite has 28% available chlorine. It requires 3 oz of muriatic acid per lb as a pH neutralizer. The addition of lithium hypochlorite increases the Total Dissolved Solids (TDS) by 35% for each 10,000 gallons of water, including the neutralizer. This results in an elevation of 16 parts per million (ppm). Lithium hypochlorite has a pH of 10.8.

What are the Characteristics of Lithium Hypochlorite?

Lithium hypochlorite is non-flammable, dust-free, and does not cloud the water or cause scale. It dissolves quickly and allows for direct addition to any pool. However, it is not possible to use it in a dry chlorine feeder or floater due to its fast dissolving nature.

Is Lithium Hypochlorite stable?

Yes, lithium hypochlorite is stable. It has a maximum storage duration of 2-3 years under appropriate conditions.

What is the Solubility of Lithium Hypochlorite?

The solubility of lithium hypochlorite is 430 grams per liter at 77° F (25° C) and 1 atm. This means that lithium hypo is extremely soluble in water. When dispersed, lithium hypochlorite typically dissolves before reaching the bottom of the pool.

How much Chlorine is in Lithium Chlorine?

Lithium chlorine, also known as lithium hypochlorite, contains either 28% or 35% available chlorine. This equates to about 14% or 17.5% chlorine by weight. The final lithium hypo product contains approximately 30% LiOCl, 34% NaCl, 20% NaSO4, and 15% other inert ingredients, resulting in about 18% chlorine or approximately 36% available chlorine.

Where is Lithium Hypochlorite used?

Lithium hypochlorite is used for disinfecting swimming pools. Lithium hypo is suitable for use in all types of pools including white plaster, colored plaster, vinyl liner, fiberglass, acrylic, and painted pools. It is also used for regular and superchlorination.

How is Lithium Hypochlorite Used?

Lithium hypochlorite is used for regular and superchlorination. It is a primary sanitizer and disinfectant, oxidizer, and algaecide. Lithium hypo also provides a persistent, long-lasting residual effect. It provides 28% FAC per lb for 10,000 gallons. The recommended FAC level is 7.5% of CYA, with a minimum of 5.0% of CYA. To achieve superchlorination or shock, it is necessary to use 10 ppm for a period of 4 hours.

What Happens When Lithium Hypochlorite is Added to Water?

When lithium hypochlorite is added to water, it reacts to produce hypochlorous acid, lithium ion, and hydroxide ion. This reaction is also described as lithium hypochlorite interacting with water to produce hypochlorous acid and lithium hydroxide. The lithium hydroxide then ionizes into a lithium ion and a hydroxyl ion.

How to increase Chlorine in the pool with Lithium Hypochlorite?

To increase chlorine in the pool with lithium hypochlorite, it must be added separately to the pool water, either by broadcasting or pre-dissolving. Adding 3.4 ounces of 28% or 4.2 ounces of 35% lithium hypochlorite per 10,000 gallons of water will increase the chlorine level by 1 ppm.  Lithium hypochlorite is a dry, granular chlorine compound that is rapidly and completely soluble, making it appropriate for superchlorination. Lithium hypo provides either 28% or 35% available chlorine. When introduced into pool or spa water, lithium hypochlorite reacts and increases the chlorine level. Lithium hypo is highly soluble and dissolves quickly when spread over the pool’s surface. However, due to its relatively low active strength and high cost, it is not commonly utilized in commercial pool facilities. The quick dissolution of lithium hypochlorite makes it ideal for use in vinyl-lined, fiberglass, or painted pools.

What are the Benefits of Lithium Hypochlorite?

The benefits of lithium hypochlorite include its stability, high solubility, and its effectiveness as a sanitizer and disinfectant. Lithium hypo is also known for its high available chlorine content and does not cloud the water or cause scale.  Lithium hypochlorite is a stable compound that has a shelf life of 2-3 years. It is suitable for regular or superchlorination due to is high solubility and quick dissolution in water. Lithium hypochlorite is typically added to water by broadcasting. This compound is non-flammable, dust-free, and does not cloud the water or cause scale.

How Can You Test Lithium Hypochlorite?

Lithium hypochlorite is typically tested weekly using DPD, FACTS, TMP Test Kit or Test Strips. On the other hand, OTO is not recommended. The testing must be done more frequently when the pool is heavily used. Lithium hypochlorite is a type of chlorine used in pools and it is important to regularly test its levels to ensure the water is safe and clean. The recommended testing methods include DPD, FACTS, TMP Test Kit or Test Strips. However, OTO is not recommended for testing lithium hypochlorite. When the pool is heavily used, it is advised to test more frequently.

How to store Lithium Hypochlorite?

Lithium hypochlorite storage capacity reaches up to 18,000 lbs in a non-sprinklered area and up to 36,000 lbs in a sprinklered area. Lithium hypochlorite is categorized under the NFPA Storage Class I and is classified as a 5.1 DOT Hazard Class. Lithium Hypochlorite is a stable compound and has a shelf life of 2-3 years. It is important to follow the storage requirements as lithium hypochlorite is classified under the NFPA Storage Class I. According to this classification, lithium hypo permits storage of up to 18,000 lbs in a non-sprinklered area and up to 36,000 lbs in a sprinklered area. Additionally, lithium hypo is classified as a 5.1 DOT Hazard Class, indicating that it is an oxidizing substance and causes or contributes to the combustion of other material.

Is Lithium Hypochlorite and Lithium Hypo the same?

Yes, lithium hypochlorite and lithium hypo are the same. Lithium hypochlorite, also known as lithium hypo, is a white powder or granule with a high pH (10.8). Lithium hypo provides 35% available chlorine and does not contain stabilizer (cyanuric acid or conditioner). Lithium hypochlorite is used for disinfecting swimming pools and is known for its high available chlorine content. Lithium hypo is manufactured by mixing chlorine gas with caustic soda and then with lithium hydroxide.